CN107265962B - A kind of super insulating aerogel foam concrete and preparation method thereof - Google Patents

Abstract

The invention discloses a super-insulation aerogel foamed concrete and a preparation method thereof, characterized in that the aerogel foamed concrete is composed of aerogel powder and foamed concrete, and the aerogel powder is composed of an internal hydrophobic layer and a foamed concrete. The surface hydrophilic layer is formed, and the thickness of the surface hydrophilic layer is 0.1-100 μm. The preparation method of the super-insulation aerogel foam concrete of the present invention comprises the following steps: (1) modifying the aerogel powder; (2) dry mixing the aerogel powder obtained in step (1) with a cementitious material, Then add water for wet mixing; (3) mix the wet mixture obtained in step (2) with a foaming agent, and stir. The aerogel foamed concrete of the invention can be widely used in the fields of wall body heat preservation, fire prevention, sound insulation and steel structure fire prevention.

Description

A kind of super insulating aerogel foam concrete and preparation method thereof

technical field

The invention relates to a preparation method of a building thermal insulation material, in particular to a super thermal insulation aerogel foamed concrete and a preparation method thereof, belonging to the fields of lightweight, thermal insulation, fire prevention, sound insulation materials and the like.

Background technique

With the progress of society, the problems of energy crisis and environmental deterioration are becoming more and more serious. In 2006, the Outline of the Eleventh Five-Year Plan for National Economic and Social Development put forward the concept of "energy saving and emission reduction" for the first time, and proposed that the energy consumption per unit of GDP should be reduced by 20% during the "Eleventh Five-Year" period (2006-2010). %, the binding target of reducing the total discharge of major pollutants by 10%. "Energy saving" promotes "emission reduction". In the total energy consumption of domestic production, building energy consumption accounts for 33%. Building energy saving is the top priority of my country's energy saving and emission reduction. According to statistics, the heat loss of the wall structure is relatively the highest, and taking thermal insulation measures to the wall is a key step in building energy conservation.

Commonly used wall insulation materials include foamed polystyrene, foamed polyurethane, rock wool, thermal insulation mortar, foamed glass, traditional foamed concrete, etc. Foamed polystyrene and foamed polyurethane have excellent thermal insulation performance, but they are flammable in case of fire and produce suffocating smoke, which seriously threatens the safety of owners; rock wool has excellent thermal insulation performance, but it fails in water and is difficult to construct; thermal insulation mortar The fire resistance is good, but the thermal conductivity is relatively high; the foamed glass is easy to slag, and the cost is high, which affects its engineering application.

Compared with existing thermal insulation materials, foamed concrete belongs to A-level thermal insulation materials, and has the advantages of high strength and low cost, but its thermal insulation performance is not as good as that of organic foam thermal insulation materials. Therefore, it is of great significance to further improve the thermal insulation performance of foamed concrete.

Aerogel is a lightweight inorganic solid material with a three-dimensional network skeleton structure and nano-scale pores, with extremely high porosity, specific surface area, extremely low density and solid content, chemical inertness and incombustibility, showing excellent It has the characteristics of light weight, thermal insulation, fire prevention, sound insulation, shock absorption and energy absorption, and the thermal conductivity can be as low as 0.013W/m·K. Therefore, if aerogel is added to foamed concrete, it is expected to break through the bottleneck that restricts further improving the thermal insulation performance of foamed concrete.

However, the following technical bottlenecks were encountered in the development of aerogel foamed concrete: (1) Due to the large difference in density between aerogel powder and concrete, during the mixing process, phase separation between the two is easy to occur, resulting in aerogelation. It is difficult for the glue to be evenly distributed in the concrete system, resulting in a serious decline in the mechanical properties of the foamed concrete, and an insignificant improvement in the thermal insulation performance; (2) During the preparation process of the foamed concrete, the aerogel nanoporous structure is easily affected by the water and cement in the concrete. Additives in the raw materials are damaged, and the excellent thermal insulation properties of the aerogel due to the nanoporous structure are lost; (3) The mechanical properties of the foamed concrete are significantly reduced due to the low interface strength between the aerogel and the cementitious material. And it is easy to cause the aerogel powder to fall off from the concrete matrix.

SUMMARY OF THE INVENTION

In view of the above technical problems, the present invention proposes a super-insulation aerogel foamed concrete and a preparation method thereof.

A super-insulation aerogel foam concrete is composed of aerogel powder and foam concrete, the aerogel powder is composed of an inner hydrophobic layer and a surface hydrophilic layer, and the thickness of the surface hydrophilic layer is 0.1-100 μm .

A preparation method of super insulating aerogel foam concrete, comprising the following steps:

(1) Modification of aerogel powder;

(2) dry mixing the aerogel powder obtained in step (1) with the gelling material, and then adding water to wet mixing;

(3) Mix the wet mixture obtained in step (2) with the foaming agent, and stir.

In one embodiment, the step (1) includes a hydrophobic modification step; the hydrophobic modification is hydrophobic modification of the aerogel powder in a closed gas-phase environment of a hydrophobic modifier; the hydrophobic modification The agent is trimethylchlorosilane, hexamethyldisilazane, hexamethyldisiloxane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, Methyldiethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(2,3-glycidoxy)propyltrimethoxysilane, γ- One or more of methacryloxypropyltrimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltriethoxysilane.

In one embodiment, the step (1) further includes a surface hydrophilic modification step; the surface hydrophilic modification is to use a surface hydrophilic modification solution to modify the surface of the hydrophobic aerogel powder; The surface hydrophilic modification solution is an aqueous solution of a surfactant and a low surface tension solvent or an aqueous solution of a low surface tension solvent; the surfactant is an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a non-ionic surfactant. One or more of the ionic surfactants; the anionic surfactants are fatty alcohol phosphates, fatty alcohol polyoxyethylene ether phosphates, alkyl sulfates, fatty alcohol polyoxyethylene ether sulfates , Glycerol fatty acid ester sulfate, sulfated ricinoleate, naphthenic sulfate, fatty amide alkyl sulfate, alkyl benzene sulfonate, alkyl sulfonate, fatty acid methyl ester ethoxylate sulfonate , one or more of fatty acid methyl ester sulfonate, fatty alcohol polyoxyethylene ether carboxylate; described cationic surfactant is aliphatic ammonium salt; described amphoteric surfactant is alkyl amino acid, carboxylate One or more of acid betaine, sulfobetaine, phosphate betaine, alkyl hydroxyamine oxide; the nonionic surfactant is aliphatic polyester, alkylphenol polyoxyethylene ether, High carbon fatty alcohol polyoxyethylene ethers, fatty acid polyoxyethylene esters, fatty acid methyl ester ethoxylates, ethylene oxide adducts of polypropylene glycol, sorbitan esters, sucrose fatty acid esters, alkyl ester amides One or more; the low surface tension solvent is one or more mixtures of acetone, n-hexane, n-pentane, n-heptane, ethanol, isopropanol, tert-butanol, propylene glycol, and glycerin.

In one embodiment, the surface hydrophilic modification step further includes a step of applying an external physical field; the step of applying an external physical field is one of far-infrared radiation, stirring, ultrasonic treatment, and ball milling.

In one embodiment, the step (1) further includes a drying treatment step; the drying treatment step is far-infrared drying, spray drying, microwave drying, atmospheric drying, supercritical drying, subcritical drying, freeze drying a kind of.

In one embodiment, the cementitious material is Portland cement, aluminate cement, sulfoaluminate cement, magnesium oxychloride cement, gypsum, lime, water glass, acrylic emulsion, polyurethane emulsion, epoxy resin One or more of emulsions, silicone resin emulsions, fluorocarbon resin emulsions, polyvinyl alcohol emulsions, and ethylene/vinyl acetate copolymer emulsions.

In one embodiment, phase change energy storage materials, light aggregates, admixtures, fibers, flame retardants, wood flour, external one or more of the agents.

In one embodiment, the phase change energy storage material is one or more of inorganic water and salt, higher aliphatic hydrocarbons, polyols, and polyhydroxy carboxylic acids covered by microcapsules; the light aggregate is One or more of ceramsite, slag, expanded vermiculite, volcanic stone, expanded perlite, vitrified microbeads, light sand, polyurethane foam particles, and polystyrene foam particles; the admixture is calcium-enhanced pulverized coal One or more of ash, grade II fly ash, silica fume, ground slag powder, phosphorus slag powder; the fibers are polystyrene fibers, polypropylene fibers, lignin fibers, alkali-resistant glass fibers, steel One or more of the fibers; the flame retardant is one or both of magnesium hydroxide and aluminum hydroxide; the admixture is the surfactant, water reducing agent, water repellent, accelerator One or more of coagulant, retarder, thickener, foam stabilizer and preservative; the water reducing agent is polycarboxylic acid water reducing agent, lignosulfonate sodium salt water reducing agent, naphthalene It is one or more of a water-reducing agent, aliphatic water-reducing agent, and amino water-reducing agent; the water-repellent agent is one or more of a stearate water-repellent agent and an organic silicon water-repellent agent; The coagulant is one or more of sodium silicate, aluminum sulfate, sodium nitrate, calcium nitrate, sodium sulfate, sodium carbonate, lithium carbonate; the retarder is citric acid, sodium polyphosphate, bone glue One or more of protein and borax; the thickener is one of methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, bentonite, white carbon black, and starch or more; the foam stabilizer is one or more of polyacrylamide, polyvinyl alcohol, silicone resin polyether emulsion, dodecyl dimethyl amine oxide, and alkyl alcohol amide; the preservative are 1,2-benzisothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 1 , One or more of 3,5-tris(2-hydroxyethyl)-s-triazine and hexahydro-1,3,5-triethyl-triazine.

In one embodiment, the foaming agent is rosin foaming agent, synthetic surfactant foaming agent, vegetable protein foaming agent, animal protein foaming agent, hydrogen peroxide foaming agent, ammonium bicarbonate foaming agent One or more of the foaming agent, azodicarbonamide foaming agent and aluminum powder foaming agent.

The above-mentioned super-insulation aerogel foam concrete has a thermal conductivity of 0.03-0.09 W/m·K and a compressive strength of 0.5-15.0 MPa, and can be widely used in the fields of wall insulation, fire prevention, sound insulation and steel structure fire prevention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific implementation disclosed below.

An embodiment of the super-insulation aerogel foam concrete of the present invention is composed of aerogel powder and foam concrete, the aerogel powder is composed of an inner hydrophobic layer and a surface hydrophilic layer, and the surface is hydrophilic The layer thickness is from 0.1 to 100 μm.

In this way, in the present invention, the aerogel powder is compounded with the foamed concrete, so that the aerogel powder is evenly distributed in the foamed concrete, the aerogel powder still maintains the nanoporous structure, and there is a gap between the aerogel powder and the concrete. Good interface bonding; compared with the existing foamed concrete on the market, the aerogel foamed concrete of the present invention significantly improves the thermal insulation performance without reducing the mechanical properties, and can be widely used in green buildings and ultra-low energy consumption and The exterior walls, self-insulation walls, floor partitions and steel structure fire protection of near-zero energy buildings.

A preparation method of super insulating aerogel foam concrete, comprising the following steps:

(1) Modification of aerogel powder;

(2) dry mixing the aerogel powder obtained in step (1) with the gelling material, and then adding water to wet mixing;

(3) Mix the wet mixture obtained in step (2) with the foaming agent, and stir.

In addition, any aerogel powder with a particle size of 1 to 10000 μm is suitable for the present invention.

In addition, step (2) of the present invention can also be dry-mixing the gelling material, then wet-mixing with water, and adding the aerogel powder obtained in step (1) during wet-mixing.

In this way, the preparation method of the aerogel foamed concrete of the present invention has the advantages of simple process, short process cycle, recycling of waste and environmental protection, etc., and is suitable for industrial production.

In this embodiment, the step (1) includes a hydrophobic modification step; the hydrophobic modification step is to hydrophobically modify the aerogel powder in a closed gas-phase environment of the hydrophobic modifier; the hydrophobic modification The agent is trimethylchlorosilane, hexamethyldisilazane, hexamethyldisiloxane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyl Diethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-(2,3-glycidoxy)propyltrimethoxysilane, γ-methyl One or more of acryloyloxypropyltrimethoxysilane and N-(β-aminoethyl)-γ-aminopropyltriethoxysilane.

In this way, since in the existing aerogel preparation methods, the precursor, the replacement solvent and the drying process have a great influence on the hydrophobicity of the aerogel, if the contact angle between the surface of the aerogel and water is greater than 90°, it is not necessary to Hydrophobic modification is carried out in advance, and surface hydrophilic modification is directly carried out; if the contact angle between the surface of the aerogel and water is less than 90°, hydrophobic modification needs to be carried out in advance; The hydrophobic modification of the colloidal powder not only significantly improves the modification effect of the aerogel powder and ensures that the internal nanoporous structure will not be destroyed during the subsequent hydrophilic modification, but also significantly improves the modification efficiency and production efficiency and reduces the production cost. .

In this embodiment, the step (1) further includes a surface hydrophilic modification step; the surface hydrophilic modification step is to use a surface hydrophilic modification solution to modify the surface of the hydrophobic aerogel powder; The surface hydrophilic modification solution is an aqueous solution of a surfactant and a low surface tension solvent or an aqueous solution of a low surface tension solvent; the surfactant is an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant One or more of the type surfactants; the anionic surfactants are fatty alcohol phosphate ester salt, fatty alcohol polyoxyethylene ether phosphate ester salt, alkyl sulfate, fatty alcohol polyoxyethylene ether sulfate, Glycerol fatty acid ester sulfate, sulfated ricinoleate, naphthenic sulfate, fatty amide alkyl sulfate, alkylbenzene sulfonate, alkyl sulfonate, fatty acid methyl ester ethoxylate sulfonate, One or more of fatty acid methyl ester sulfonate and fatty alcohol polyoxyethylene ether carboxylate; the cationic surfactant is aliphatic ammonium salt; the amphoteric surfactant is alkyl amino acid, carboxylic acid One or more of betaine, sulfobetaine, phosphobetaine, and alkyl hydroxyamine oxide; the nonionic surfactant is aliphatic polyester, alkylphenol polyoxyethylene ether, high One of carbon fatty alcohol polyoxyethylene ether, fatty acid polyoxyethylene ester, fatty acid methyl ester ethoxylate, ethylene oxide adduct of polypropylene glycol, sorbitan ester, sucrose fatty acid ester, alkyl ester amide one or more; the low surface tension solvent is one or more of acetone, n-hexane, n-pentane, n-heptane, ethanol, isopropanol, tert-butanol, propylene glycol, and glycerol.

In this way, the use of an aqueous solution of a surfactant and a low surface tension solvent or an aqueous solution of a low surface tension solvent has a surface synergistic hydrophilic modification effect during the hydrophilic modification treatment of the surface of the hydrophobic aerogel powder, which can significantly improve the performance of the hydrophobic aerogel powder. The wetting and spreading rate of the surface hydrophilic modification solution on the surface of the aerogel powder significantly slows down the wetting and spreading to the inside of the aerogel powder. By adjusting the thickness of the hydrophilic layer on the surface of the powder, the low surface tension solvent not only has a surface synergistic hydrophilic modification effect with water and surfactants, but also can greatly reduce the hydrophilic modification entering the nanopores of the surface of the aerogel powder. The capillary force of the solution can easily evaporate the hydrophilic modification solution in the nanopores of the surface layer of the aerogel powder through the drying process without destroying its nanoporous structure. The hydrophilic and surface hydrophilic layer still retains the nanoporous structure and the surface hydrophilic layer thickness is 0.1~100μm, which has good interface bonding with the gelling material; this process has the advantages of simple steps, short cycle and high production efficiency Features, suitable for industrial production.

In this embodiment, the surface hydrophilic modification step further includes a step of applying an external physical field; the step of applying a physical field is one of far-infrared radiation, stirring, ultrasonic treatment, and ball milling.

In this way, the action of the external physical field can significantly improve the activity of the surface hydrophilic modification solution and the contact probability with the aerogel powder, reduce the amount of surfactant, improve the surface hydrophilic modification rate of the aerogel powder, and reduce the cost. ,Increase productivity.

In this embodiment, the step (1) further includes a drying treatment step; the drying treatment step is one of far-infrared drying, spray drying, microwave drying, atmospheric drying, supercritical drying, subcritical drying, and freeze drying. kind.

In this way, if the hydrophilically modified aerogel powder is compounded with the gelling material, the residual hydrophilic modification solution on the surface will affect the interface bonding, and it needs to be pre-dried; the above drying process is used to ensure that the aerogel powder is Under the premise that the nanopore structure of the surface layer is not destroyed, the residual surface hydrophilic modification solution in the nanopores of the surface layer of the aerogel powder is evaporated, so as to improve the interface bonding strength between the aerogel powder and the gelling material.

In this embodiment, the cementitious material is Portland cement, aluminate cement, sulfoaluminate cement, magnesium oxychloride cement, gypsum, lime, water glass, acrylic emulsion, polyurethane emulsion, epoxy resin emulsion, One or more of silicone resin emulsion, fluorocarbon resin emulsion, polyvinyl alcohol emulsion, and ethylene/vinyl acetate copolymer emulsion.

In this embodiment, phase change energy storage materials, light aggregates, admixtures, fibers, flame retardants, wood flour, and additives may also be added to the step (2) and/or the step (3). one or more of.

In this way, the step (2) of the present invention adopts a two-step mixing process of dry mixing and wet mixing to solve the problem of delamination caused by mixing the aerogel powder and other materials due to the large specific gravity difference, and realize the modified aerogel powder. The uniform mixing in the concrete, while reducing the influence of the aerogel powder on the foaming process, is beneficial to control the foaming quality and achieve low thermal conductivity.

In this embodiment, the phase change energy storage material is one or more of inorganic water and salts, higher aliphatic hydrocarbons, polyols, and polyhydroxy carboxylic acids covered by microcapsules; the lightweight aggregate is ceramsite , one or more of slag, expanded vermiculite, volcanic stone, expanded perlite, vitrified microbeads, light sand, polyurethane foam particles, polystyrene foam particles; the admixture is calcium-enhanced fly ash, One or more of Class II fly ash, silica fume, ground slag powder, and phosphorus slag powder; the fibers are polystyrene fibers, polypropylene fibers, lignin fibers, alkali-resistant glass fibers, and steel fibers. one or more; the flame retardant is one or both of magnesium hydroxide and aluminum hydroxide; the admixture is the surfactant, water reducing agent, water repellent, coagulant , one or more of retarders, thickeners, foam stabilizers, and preservatives; the water reducing agent is a polycarboxylic acid water reducing agent, a sodium lignosulfonate water reducing agent, a naphthalene water reducing agent One or more of water-reducing agent, aliphatic water-reducing agent and amino water-reducing agent; the water-repellent agent is one or more of stearate water-repellent agent and silicone water-repellent agent; the water-repellent agent The coagulant is one or more of sodium silicate, aluminum sulfate, sodium nitrate, calcium nitrate, sodium sulfate, sodium carbonate, and lithium carbonate; the retarder is citric acid, sodium polyphosphate, bone glue protein, One or more of borax; the thickener is one or more of methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, bentonite, silica, and starch The foam stabilizer is one or more of polyacrylamide, polyvinyl alcohol, silicone resin polyether emulsion, dodecyl dimethyl amine oxide, and alkyl alcohol amide; the preservative is 1 , 2-benzisothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 1,3 , One or more of 5-tris(2-hydroxyethyl)-s-triazine and hexahydro-1,3,5-triethyl-triazine.

In this way, the phase change energy storage material can absorb or release a large amount of heat energy through phase change, and has the function of energy storage. The aerogel foamed concrete of the present invention is used for the building wall, which can adjust the indoor temperature of the building, improve the building comfort, and save energy. , and the addition of phase change energy storage materials can improve the freeze-thaw resistance of the aerogel foamed concrete of the present invention; light aggregates have low density, high compressive strength, and good thermal insulation properties, and adding light aggregates can improve the The mechanical properties and thermal insulation properties of aerogel foam concrete do not significantly increase or decrease its density; the use of admixtures can improve the workability and cohesion of concrete, and reduce the slump of concrete, which is beneficial to the performance of aerogel foam concrete. The pore size distribution is uniform, thereby improving the mechanical properties and thermal insulation properties of aerogel foam concrete; and the use of admixtures is conducive to the use of industrial waste, reducing the cost of aerogel foam concrete, saving energy and recycling waste; adding fibers can improve aerogelation. The mechanical properties of foamed concrete such as flexural resistance can be improved; adding flame retardants can improve the fire rating of the aerogel foamed concrete of the present invention. Since the flame retardants such as magnesium hydroxide and aluminum hydroxide have a dehydration and endothermic reaction in case of fire, the matrix can be extended for a long time. The rate of temperature increase; adding wood powder can improve the strength between aerogel foam concrete and anchors and screws; adding surfactants can improve the wetting efficiency of cementitious materials on surfaces such as fibers and lightweight aggregates, thereby improving Interface bonding strength between cementitious material and fiber, cementitious material and lightweight aggregate; adding water reducer can improve the fluidity and slump of concrete, reduce water consumption, and improve the mechanical properties of aerogel foam concrete; adding water-repellent It can significantly reduce the water absorption of aerogel foamed concrete, especially the aerogel foamed concrete with through-hole structure, and improve the freeze-thaw resistance and weather resistance of aerogel foamed concrete. The curing rate can reduce the initial setting time of aerogel foam concrete, reduce the pore size of aerogel foam concrete, make the pore size distribution of aerogel foam concrete uniform, and improve the mechanical properties and thermal insulation performance of aerogel foam concrete; adding retarder can Slow down the curing rate of the cementitious material. When using gypsum, because the curing rate of gypsum is too fast, it is necessary to add a retarder to adjust the hardening time; adding a thickener can increase the viscosity of concrete and improve the stability and porosity of foam concrete cells. The shape of the cells of the aerogel foam concrete is mostly regular spherical, thereby improving the mechanical properties and thermal insulation performance of the aerogel foam concrete; adding a foam stabilizer can improve the cell stability and porosity of the aerogel foam concrete. , and then improve the mechanical properties and thermal insulation properties of aerogel foam concrete; adding preservatives can avoid mildew of aerogel foam concrete and improve its service life and durability.

In this embodiment, the foaming agent is rosin foaming agent, synthetic surfactant foaming agent, vegetable protein foaming agent, animal protein foaming agent, hydrogen peroxide foaming agent, ammonium bicarbonate foaming agent, One or more of azodicarbonamide foaming agent and aluminum powder foaming agent.

In this way, the type of foaming agent has a great influence on the pore type, pore size distribution, water absorption and thermal insulation performance of the aerogel foamed concrete. Preparation of aerogel foam concrete by foaming method. The physical foaming method is to use an air compressor or mechanical stirring method to mix a physical foaming agent (one of rosin foaming agent, synthetic surfactant foaming agent, vegetable protein foaming agent, animal protein foaming agent) , polymer emulsion (one of acrylic emulsion, polyurethane emulsion, epoxy resin emulsion, silicone resin emulsion, fluorocarbon resin emulsion, polyvinyl alcohol emulsion, ethylene/vinyl acetate copolymer emulsion) and foaming agent composed of water The solution or the foaming agent solution composed of physical foaming agent and water is prepared into prefabricated foam, and then the prefabricated foam is mixed with the wet mixture, and the aerogel foamed concrete is obtained by mechanical stirring. The chemical foaming method is to mix the wet mixture with the wet mixture. Chemical foaming agent (one of hydrogen peroxide foaming agent, ammonium bicarbonate foaming agent, azodicarbonamide foaming agent, and aluminum powder foaming agent) is mixed and stirred to obtain aerogel foamed concrete.

The above-mentioned super-insulation aerogel foam concrete has a thermal conductivity of 0.03-0.09 W/m·K and a compressive strength of 0.5-15.0 MPa, and can be widely used in the fields of wall insulation, fire prevention, sound insulation and steel structure fire prevention.

The following is the specific embodiment part.

Example 1

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder to be treated and water, the detection result is 55°, and then place the SiO ₂ aerogel powder with a particle size of 56 μm in a vacuum heating In the furnace, the weighed hexamethyldisilazane was placed in a vacuum heating furnace with a container, heated and gasified, and hydrophobically modified for 1.5h to obtain a hydrophobic SiO ₂ aerogel powder, which was detected with a contact angle measuring instrument. The contact angle between the surface of the hydrophobic SiO ₂ aerogel powder and water is 147°;

(2) At room temperature, weigh ethanol, n-hexane and deionized water in a mass ratio of 1:1:100, mix them evenly, and prepare a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after being ball-milled for 25 minutes, it is taken out and filtered;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it at a temperature of 120 ° C for 0.5 h, and cool it to below 50 ° C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested, and the test result showed that the thickness of the surface hydrophilic layer was 7.9 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, ceramsite, redispersible latex powder, hydroxymethyl cellulose, polycarboxylate water reducer in step (4) in turn according to the proportions , sodium sulfate, aluminum hydroxide, microcapsule-coated paraffin, and dry mixing to obtain a dry mixture;

(6) adding water and hexahydro-1,3,5-triethyl-triazine preservative to the dry mixture obtained in step (5), and performing wet mixing to obtain a wet mixture;

(7) Use a foaming machine to foam the aqueous solution containing the animal protein foaming agent, and the volume ratio of the animal protein foaming agent to water is 1:20 to obtain a foam;

(8) Mix the wet mixture obtained in step (6) with the foam, and stir mechanically for ₁ min to obtain SiO ₂ aerogel foamed concrete. Standard maintenance performance indicators.

Table 1 Performance index of _SiO2 aerogel foam concrete

Example 2

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder to be treated and water, the detection result is 45°, and then place the SiO ₂ aerogel powder with a particle size of 67 μm in a vacuum heating In the furnace, the weighed trimethylchlorosilane was placed in a vacuum heating furnace with a container, heated and gasified, and hydrophobically modified for 1.5 h to obtain a hydrophobic SiO ₂ aerogel powder, and the hydrophobic SiO was detected with a contact angle meter. _2. The contact angle between the surface of the aerogel powder and water, the test result is 146°;

(2) At room temperature, weigh sodium aliphatic alcohol polyoxyethylene ether sulfate, sodium alkylbenzene sulfonate, n-hexane and deionized water in a mass ratio of 1:1:1000, mix them evenly, and configure the surface to be hydrophilically modified. solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is placed in a container made of a filter screen, immersed in the surface hydrophilic modification solution together, and taken out after 2 minutes;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a blast drying oven, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested. The test result showed that the thickness of the surface hydrophilic layer was 1.3 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, ceramsite, redispersible latex powder, hydroxyethyl cellulose, polycarboxylate water reducer in step (4) in turn according to the proportions , sodium nitrate, polypropylene fibers, and dry mixing to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) Foam preparation, use a foaming machine to foam the aqueous solution containing vegetable protein foaming agent, and the volume ratio of vegetable protein foaming agent and water is 1:30 to obtain foam;

(8) Mix the wet mixture obtained in step (6) with the foam, and stir mechanically for 1 min to obtain SiO ₂ aerogel foamed concrete. Table 2 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 2 Performance index of _SiO2 aerogel foam concrete

Example 3

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder to be treated and water, the detection result is 45°, and then place the SiO ₂ aerogel powder with a particle size of 0.1mm in a vacuum In the heating furnace, the weighed hexamethyldisilazane was placed in a vacuum heating furnace with a container, heated for gasification, and hydrophobically modified for 1.5 hours to obtain a hydrophobic SiO ₂ aerogel powder. The contact angle between the surface of the hydrophobic SiO ₂ aerogel powder and water was detected, and the detection result was 146°;

(2) At room temperature, weigh n-hexane, sodium alkylbenzene sulfonate and deionized water in a mass ratio of 1:4:10, mix them evenly, and prepare a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is placed in a container made of a filter screen, immersed in the surface hydrophilic modification solution together, and taken out after 1 minute;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it at a temperature of 120 ° C for 0.5 h, and cool it to below 50 ° C with the furnace After taking it out and breaking it, the cross section of the SiO ₂ aerogel powder was tested, and the test result showed that the thickness of the surface hydrophilic layer was 99.7 μm;

(5) Weigh the SiO ₂ aerogel powder in step (4), 425 ordinary Portland cement, ceramsite, starch, polycarboxylate water-reducing agent, and aluminum sulfate in turn according to the proportion, and carry out dry mixing to obtain dry mix;

(6) adding water and the acrylic acid emulsion to the dry mix obtained in step (5) for wet mixing to obtain a wet mix;

(7) Foam preparation, use a foaming machine to foam the aqueous solution containing sodium lauryl sulfate foaming agent and acrylic emulsion, and the volume ratio of sodium lauryl sulfate foaming agent and water is 1:80. get foam;

(8) Mix the wet mixture obtained in step (6) with the foam, and stir mechanically for 3 minutes to obtain SiO ₂ aerogel foamed concrete. Table 3 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 3 Performance index of _SiO2 aerogel foam concrete

Example 4

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder to be treated and water, the detection result is 31°, and then place the SiO ₂ aerogel powder with a particle size of 1.2 mm in a vacuum In the heating furnace, the weighed trimethylchlorosilane was placed in a vacuum heating furnace with a container, heated and gasified, and hydrophobically modified for 1.5 hours to obtain a hydrophobic SiO ₂ aerogel powder, and the hydrophobicity was detected by a contact angle meter. The contact angle between the surface of SiO ₂ aerogel powder and water, the detection result is 150°;

(2) At room temperature, weigh n-hexane, sodium alkyl benzene sulfonate and deionized water in a mass ratio of 1:0.5:1000, mix them evenly, and prepare a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is placed in a container made of a filter screen, immersed in the surface hydrophilic modification solution together, and taken out after 1 minute;

(4) Place the SiO ₂ aerogel sheet containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace. Take it out and test the cross section of the SiO ₂ aerogel powder. The test result shows that the thickness of the surface hydrophilic layer is 0.1 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, vitrified microbeads, redispersible latex powder, hydroxymethyl cellulose, and polycarboxylates in step (4) in turn according to the proportions. Water agent, lithium carbonate and silicone water repellent are dry mixed to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) Foam preparation, use a foaming machine to foam the aqueous solution containing animal protein foaming agent, and the volume ratio of animal protein foaming agent and water is 1:15 to obtain foam;

(8) Mix the wet mixture obtained in step (6) with the foam, and stir mechanically for 1 min to obtain SiO ₂ aerogel foamed concrete. Table 4 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 4 Performance index of _SiO2 aerogel foam concrete

Example 5

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder with a particle size of 77 μm to be treated and water, and the detection result is 140°, then the SiO ₂ aerogel powder has hydrophobicity;

(2) At room temperature, weigh sodium lauryl sulfate, acetone and deionized water in a mass ratio of 1:0.6:150, mix them evenly, and configure a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after being ball-milled for 25 minutes, it is taken out and filtered;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a blast drying oven, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested. The test result showed that the thickness of the hydrophilic layer on the surface was 6.9 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, fly ash, ceramsite, redispersible latex powder, hydroxyethyl cellulose, polycarboxylic acid in step (4) in turn according to the proportions water-reducing agent, sodium sulfate, and dry mixing to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) Mix the wet mixture obtained in step (6) with an aluminum powder foaming agent, stir mechanically for 10 minutes, and foam to obtain SiO ₂ aerogel foamed concrete. Table 5 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 5 Performance index of _SiO2 aerogel foam concrete

Example 6

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder with a particle size of 75 μm to be treated and water, and the detection result is 141°, then the SiO ₂ aerogel powder has hydrophobicity;

(2) At room temperature, weigh nonylphenol polyoxyethylene ether, n-hexane and deionized water in a mass ratio of 1:0.3:100, mix them evenly, and prepare a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after ball milling for 15 minutes, it is taken out and filtered;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it at a temperature of 120 ° C for 0.5 h, and cool it to below 50 ° C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested. The test result showed that the thickness of the surface hydrophilic layer was 11.1 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, fly ash, ceramsite, redispersible latex powder, starch, polycarboxylate water reducer in step (4) in turn according to the proportions , sodium sulfate, silicone water repellent, and dry mixing to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) The wet mixture obtained in step (6) is mixed with hydrogen peroxide foaming agent, mechanically stirred for 2 minutes, and foamed to obtain SiO ₂ aerogel foamed concrete. Table 6 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 6 Performance index of _SiO2 aerogel foam concrete

Example 7

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder with a particle size of 0.3 mm to be treated and water, and the detection result is 148°, then the SiO ₂ aerogel powder has hydrophobicity ;

(2) At room temperature, weigh fatty alcohol polyoxyethylene ether ammonium sulfate, n-hexane, ethanol and deionized water in a mass ratio of 1:0.4:0.3:130, mix them evenly, and prepare a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after mechanical stirring for 15 minutes, the rotation speed is 2500 rpm, and then filtered;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it at a temperature of 120 ° C for 0.5 h, and cool it to below 50 ° C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested. The test result showed that the thickness of the surface hydrophilic layer was 11.1 μm;

(5) Weigh the SiO ₂ aerogel powder, 525 ordinary Portland cement, sulfoaluminate cement, ceramsite, redispersible latex powder, hydroxymethyl cellulose, polymer Carboxylic acid water reducing agent and sodium sulfate are dry mixed to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) The wet mixture obtained in step (6) is mixed with ammonium bicarbonate foaming agent, mechanically stirred for 2 minutes, and foamed to obtain SiO ₂ aerogel foamed concrete. Table 7 shows the performance indexes of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 7 Performance index of _SiO2 aerogel foam concrete

Example 8

The _TiO2 aerogel foam concrete was prepared using the following steps:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the TiO ₂ aerogel powder with a particle size of 59 μm to be treated and water, and the detection result is 145°, then the TiO ₂ aerogel powder has hydrophobicity;

(2) At room temperature, weigh acetone, n-hexane and deionized water in a mass ratio of 1:0.8:120, mix them evenly, and configure the surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic _{TiO 2} aerogel powder and the surface hydrophilic modification solution 1:3, weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after mechanical stirring for 15 minutes, the rotation speed is 2000 rpm, and then filtered;

(4) Place the TiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a blast drying oven, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace After taking it out, the cross section of the TiO ₂ aerogel powder was tested, and the test result showed that the thickness of the surface hydrophilic layer was 8.4 μm;

(5) Weigh the TiO ₂ aerogel powder, 425 ordinary Portland cement, fly ash, ceramsite, dispersible latex powder, hydroxymethyl cellulose, polycarboxylic acid in step (4) in turn according to the proportions water-reducing agent, sodium sulfate, and silicone water-repellent agent, and dry mixing to obtain a dry mixture;

(6) adding water to the dry mix obtained in step (5) and performing wet mixing to obtain a wet mix;

(7) The wet mixture obtained in step (6) is mixed with hydrogen peroxide foaming agent, mechanically stirred for 2 minutes, and foamed to obtain TiO ₂ aerogel foamed concrete. Table 8 is the performance index of the TiO ₂ aerogel foam concrete prepared in this example after 28d standard curing.

Table 8 Performance indexes of TiO ₂ aerogel foam concrete

Example 9

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder to be treated and water, the detection result is 31°, and then place the SiO ₂ aerogel powder with a particle size of 22 μm in a vacuum heating In the furnace, the weighed hexamethyldisilazane was placed in a vacuum heating furnace with a container, heated and gasified, and hydrophobically modified for 2.5h to obtain a hydrophobic SiO ₂ aerogel powder, which was detected by a contact angle measuring instrument. The contact angle between the surface of the hydrophobic SiO ₂ aerogel powder and water, the test result is 150°;

(2) At room temperature, weigh n-hexane, glycerol and deionized water in a mass ratio of 1:0.5:1000, mix them evenly, and configure into a surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is placed in a container made of a filter screen, immersed in the surface hydrophilic modification solution together, and taken out after 1 minute;

(4) Place the SiO ₂ aerogel sheet containing the hydrophilic modification solution on the surface obtained in step (3) in a far-infrared drying furnace, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace. Take it out and test the cross section of the SiO ₂ aerogel powder. The test result shows that the thickness of the surface hydrophilic layer is 2.2 μm;

(5) Weigh the SiO ₂ aerogel powder, 425 ordinary Portland cement, hemihydrate gypsum, polycarboxylate water reducing agent, sodium citrate, magnesium hydroxide, microcapsules in step (4) in turn according to the proportions. The octadecane is coated, and dry mixing is carried out to obtain a dry mixture;

(6) adding water and the acrylic acid emulsion to the dry mix obtained in step (5) for wet mixing to obtain a wet mix;

(7) Foam preparation, using a foaming machine to foam a foaming agent solution composed of a foaming agent, an acrylic emulsion and water, and the volume ratio of the animal protein foaming agent and water is 1:0.05:80 to obtain a foam body;

(8) Mix the wet mixture obtained in step (6) with the foam, and stir mechanically for 1 min to obtain SiO ₂ aerogel foamed concrete. Table 9 is the performance index of the SiO ₂ aerogel foamed concrete prepared in this example after 28d standard curing.

Table 9 Performance index of SiO ₂ aerogel foam concrete

Example 10

The following steps were used to prepare _SiO2 aerogel foam concrete:

(1) Use a contact angle measuring instrument to detect the contact angle between the surface of the SiO ₂ aerogel powder with a particle size of 177 μm and water, and the detection result is 141°, then the SiO ₂ aerogel powder has hydrophobicity;

(2) At room temperature, weigh acetone and deionized water in a mass ratio of 1:100, mix them evenly, and configure the surface hydrophilic modification solution;

(3) According to the volume ratio of the hydrophobic SiO ₂ aerogel powder and the surface hydrophilic modification solution of 1: ₃ , weigh the surface modification solution and pour it into the corresponding container. The aerogel powder is mixed with the surface hydrophilic modification solution, and after being ball-milled for 25 minutes, it is taken out and filtered;

(4) Place the SiO ₂ aerogel powder containing the hydrophilic modification solution on the surface obtained in step (3) in a blast drying oven, dry it for 0.5 h at a temperature of 120 °C, and cool it to below 50 °C with the furnace After taking it out, the cross section of the SiO ₂ aerogel powder was tested, and the test results showed that the thickness of the surface hydrophilic layer was 6.5 μm;

(5) Weigh the SiO ₂ aerogel powder, fly ash, redispersible latex powder, hydroxyethyl cellulose, polycarboxylate water reducing agent and polypropylene fiber in step (4) in sequence according to the proportions, and carry out Dry mixing to obtain a dry mixture;

(6) adding water glass and water to the dry mixture obtained in the step (5) and performing wet mixing to obtain a wet mixture;

(7) The wet mixture obtained in step (6) is mixed with an aluminum powder foaming agent, mechanically stirred for 5 minutes, and foamed to obtain SiO ₂ aerogel foamed concrete. Table 10 is the performance index of the SiO ₂ aerogel foam concrete prepared in this example after it is completely hardened.

Table 10 Performance index of SiO ₂ aerogel foam concrete

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, The simplification should be equivalent replacement manners, which are all included in the protection scope of the present invention.

Claims (1)

1. A preparation method of super heat-insulating aerogel foam concrete adopts the following steps to prepare SiO₂Aerogel foam concrete:

(1) detection of SiO to be treated by contact Angle measuring apparatus₂The contact angle of the surface of the aerogel powder and water is 55 degrees, and then the SiO with the particle size of 56 mu m is used₂Placing the aerogel powder in a vacuum heating furnace, placing the weighed hexamethyldisilazane in the vacuum heating furnace by using a container, heating and gasifying, and carrying out hydrophobic modification for 1.5h to obtain hydrophobic SiO₂Aerogel powder, detecting hydrophobic SiO with contact angle measuring instrument₂The contact angle between the surface of the aerogel powder and water is 147 degrees;

(2) weighing ethanol, n-hexane and deionized water according to the mass ratio of 1:1:100 at room temperature, uniformly mixing, and preparing a surface hydrophilic modification solution;

(3) according to hydrophobic SiO₂Weighing the surface hydrophilic modification solution according to the volume ratio of aerogel powder to the surface hydrophilic modification solution of 1:3, pouring the surface hydrophilic modification solution into a corresponding container, and adding the hydrophobic SiO obtained in the step (1)₂Mixing the aerogel powder with the surface hydrophilic modification solution, performing ball milling treatment for 25min, taking out and filtering;

(4) SiO with the surface containing hydrophilic modification solution obtained in the step (3)₂Placing aerogel powder in far infrared drying furnaceDrying at 120 deg.C for 0.5 hr, cooling to below 50 deg.C, taking out, and treating with SiO₂The cross section of the aerogel powder is detected, and the detection result shows that the thickness of the surface hydrophilic layer is 7.9 mu m;

(5) sequentially weighing the SiO in the step (4) according to the mixture ratio₂Dry mixing aerogel powder, 425 ordinary portland cement, ceramsite, redispersible latex powder, hydroxymethyl cellulose, polycarboxylic acid water reducer, sodium sulfate, aluminum hydroxide and microcapsule-coated paraffin to obtain a dry mixture;

(6) adding water and hexahydro-1, 3, 5-triethyl-triazine preservative into the dry mixture obtained in the step (5) for wet mixing to obtain a wet mixture;

(7) foaming the aqueous solution containing the animal protein foaming agent by using a foaming machine, wherein the volume ratio of the animal protein foaming agent to water is 1:20, and preparing a foam;

(8) mixing the wet mixture obtained in the step (6) with the foam obtained in the step (7), and mechanically stirring for 1min to obtain SiO₂Aerogel foam concrete.