Lightweight and high-efficiency thermal insulation mortar and preparation method thereof

Abstract

This invention provides a lightweight and high-efficiency thermal insulation mortar and its preparation method, relating to the field of building insulation materials technology. The mortar comprises: 28-40 parts of cementitious material, 29-35.75 parts of water, 16-35 parts of hydrophobic aerogel particles, 5-9 parts of foam, 0.5-2 parts of water-reducing agent, 0.2-1.5 parts of cellulose ether, 0.1-0.5 parts of redispersible latex powder, and 0.2-0.7 parts of expanding agent. This invention uses hydrophobic aerogel particles as thermal insulation aggregate. Due to the low density and extremely low thermal conductivity of aerogel particles, the prepared thermal insulation mortar exhibits lightweight and highly efficient thermal insulation performance compared to traditional thermal insulation mortars. The incorporation of foam not only improves the workability of the thermal insulation mortar but also generates more uniform and microscopic closed pores in the mortar, further reducing the density and thermal conductivity of the thermal insulation mortar.

Description

Technical Field

[0001] This invention relates to the field of building insulation materials technology, and more specifically, to a lightweight and high-efficiency thermal insulation mortar and its preparation method. Background Technology

[0002] Building envelope insulation is considered a highly efficient and simple passive building energy-saving method, and a key technology for achieving ultra-low or near-zero energy consumption and reducing carbon emissions. Improving the thermal performance of the building envelope using superior building insulation materials can effectively reduce the building's heating / cooling load, which is also an important means of reducing building energy consumption. Commonly used insulation materials include insulation boards (EPS polystyrene board + rock wool board) and insulation mortar. In addition, silica aerogel has stable chemical properties, and its main component is generally amorphous silica. Due to its excellent performance, silica aerogel is considered the most suitable material for manufacturing cement-based thermal insulation composite materials. Silica aerogel insulation mortar is a new type of insulation material that has been developed in recent years.

[0003] In the prior art, CN118005363A discloses a method for preparing hydrophobic thermal insulation mortar: 5-15 parts of hemihydrate phosphogypsum, 10-20 parts of hollow glass microspheres, 0.5-1.5 parts of polypropylene fiber, 0.1-0.2 parts of hydroxypropyl methylcellulose, 1-2.5 parts of redispersible latex powder, and 1-2 parts of a setting accelerator are dry-mixed to obtain a dry mixture; 60-80 parts of aerogel slurry are mixed with the dry mixture to obtain the thermal insulation mortar. The aerogel thermal insulation mortar has a thermal conductivity of 0.040-0.051 W / (m·K) and a density of 230-248 kg / m³. 3 .

[0004] CN106904994B discloses a method for manufacturing honeycomb thermal insulation mortar: 110-130 parts of silica micropowder, 5-6 parts of silica aerogel, 13-15 parts of polystyrene particles, 3.8-5.8 parts of dispersible latex powder, 0.12-0.19 parts of cellulose hydroxypropyl methyl ether, and 3-3.5 parts of foaming agent are mixed and stirred to form a uniform dry powder; then 48 parts of water are added and stirred evenly to obtain honeycomb granular mortar. The thermal conductivity of the honeycomb granular mortar is 0.032-0.071 W / (m·K), and the density is 140-280 kg / m³. 3 .

[0005] CN107512926B discloses a foamed aerogel thermal insulation mortar: SiO2 aerogel modified with a silane coupling agent is prepared by the following steps: (1) a silane coupling agent solution is prepared with water, and the mass fraction of the obtained silane coupling agent solution is 5-10%; (2) SiO2 aerogel is added to the silane coupling agent solution and mixed to prepare a modified SiO2 aerogel dispersion, wherein the amount of SiO2 aerogel added is 10-45% of the total mass of the silane coupling agent solution. The thermal conductivity of the foamed aerogel thermal insulation mortar is 0.031 W / (m·K), and the density is 230 kg / m³. 3 .

[0006] The hydrophobic thermal insulation mortar disclosed in CN118005363A aims to solve the technical problems of poor thermal insulation performance and poor hydrophobicity. The thermal insulation mortars disclosed in CN106904994B and CN107512926B aim to solve the problem of poor thermal insulation performance of thermal insulation mortar. Although the aerogel thermal insulation mortar disclosed in the prior art has a lower thermal conductivity than traditional thermal insulation mortar, it is not significant enough, and the density is relatively large. It has not made further breakthroughs in the thermal conductivity of aerogel thermal insulation mortar.

[0007] Therefore, how to further reduce the density and thermal conductivity of thermal insulation mortar to improve its performance has become an urgent technical problem to be solved. Summary of the Invention

[0008] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies, and discloses a lightweight and high-efficiency thermal insulation mortar and its preparation method, which further reduces the density and thermal conductivity of the thermal insulation mortar, and improves the utilization rate of raw materials and thermal insulation performance.

[0009] The first aspect of the present invention discloses a lightweight and efficient thermal insulation mortar, comprising: 28-40 parts by weight of cementitious material, 29-35.75 parts by weight of water, 16-35 parts by weight of hydrophobic aerogel particles, 5-9 parts by weight of foam, 0.5-2 parts by weight of water-reducing agent, 0.2-1.5 parts by weight of cellulose ether, 0.1-0.5 parts by weight of redispersible latex powder, and 0.2-0.7 parts by weight of expansion agent.

[0010] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the cementing material is sulfoaluminate cement or composite silicate cement, wherein the composite silicate cement includes ordinary silicate cement, gypsum, mineral powder and silica fume, and the mass ratio between them is 1:(3-5):(2-4):(0.3-1).

[0011] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the cellulose ether is at least one of hydroxyethyl methyl cellulose ether, hydroxymethyl cellulose ether, hydroxypropyl methyl cellulose ether, and hydroxyethyl cellulose ether; the cellulose ether is used to retain water, thicken, and help the hydrophobic aerogel particles disperse in the mortar.

[0012] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the redispersible latex powder is one of a copolymer of ethylene and vinyl acetate, a copolymer of vinyl acetate and ethylene tert-carbonate, or a copolymer of acrylic acid; the expanding agent is one of calcium sulfoaluminate, calcium oxide, or calcium sulfoaluminate-calcium oxide, used to compensate for the shrinkage of the prepared mortar during the hardening process.

[0013] In this technical solution, redispersible latex powder is used to improve the workability and mechanical properties of the slurry after hardening: redispersible latex powder acts as a lubricant for the construction of the prepared slurry, improves the affinity for water and viscosity, improves the workability of the slurry, and improves the wear resistance, crack resistance and toughness of the material after drying.

[0014] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the mass ratio between cellulose ether, redispersible latex powder and expanding agent is (7-38):(2-19):(3-21).

[0015] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the amount of water-reducing agent is 1-5 wt% of the mass of the cementitious material; the water-reducing agent is a polycarboxylate high-performance water-reducing agent with a water reduction rate of 25-35%, a pH value of 6.5, and a solid content of 20-60%.

[0016] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the amount of hydrophobic aerogel particles is 75-95 vol% of the total mortar volume; the hydrophobic aerogel particles are hydrophobic silica aerogel particles produced by supercritical drying, with a particle size of 2-4 mm and a bulk density of 0.06-0.1 g / cm³. 3 It has a porosity of 90-98% and a thermal conductivity of 0.015-0.026 W / (m·K) at an average temperature of 25℃.

[0017] According to the lightweight and high-efficiency thermal insulation mortar disclosed in this invention, preferably, the amount of foam is 15%-24wt% of the mass of the cementitious material; the foam is foam obtained by physical foaming of a foaming agent, wherein the foaming agent is one or more of rosin-based foaming agents, synthetic surfactant foaming agents, animal protein foaming agents, and plant protein foaming agents.

[0018] A second aspect of the present invention also discloses a method for preparing lightweight and high-efficiency thermal insulation mortar, comprising: preparing raw materials according to the material ratio of lightweight and high-efficiency thermal insulation mortar provided by any of the above technical solutions, and processing them through the following steps: Dry material mixing: Mix the gelling material, cellulose ether, redispersible latex powder and expansion agent evenly to obtain a dry powder; Add water-reducing agent: After adding the water-reducing agent to water and stirring evenly, add the mixed liquid to the dry powder and stir until there are no lumps to obtain wet slurry; Adding aerogel particles: Add hydrophobic silica aerogel particles to the wet slurry and stir; Adding foam: Before the hydrophobic silica aerogel particles are completely coated by the slurry, add the foam generated by the foaming agent and continue stirring until there is no foam residue on the surface of the slurry to obtain the finished thermal insulation mortar.

[0019] The method for preparing lightweight and high-efficiency thermal insulation mortar disclosed in this invention preferably further includes: Material molding: The finished thermal insulation mortar is poured into a mold and cured at room temperature and humidity to obtain the molded material. Room temperature and humidity refer to a temperature of 10-30℃ and a humidity of 50-85%RH. The thermal conductivity of the finished thermal insulation mortar is 0.018-0.030 W / (m·K), and the dry density is 137-160 kg / m³. 3 The compressive strength at 28 days is 23.6-42.1 kPa.

[0020] The beneficial effects of the present invention include at least the following: This invention uses hydrophobic aerogel particles as insulating aggregate. Due to the low density and extremely low thermal conductivity of aerogel particles, the prepared insulating mortar exhibits lightweight and highly efficient thermal insulation properties compared to traditional insulating mortars. The addition of foam not only improves the workability of the insulating mortar but also creates more uniform and microscopic closed pores within the mortar, further reducing its density and thermal conductivity.

[0021] The present invention adds appropriate amounts of cellulose ether and latex powder to the mortar. Its functions are as follows: (1) The water-retaining and thickening effect of cellulose ether not only effectively inhibits the sedimentation of aerogel particles, making the aerogel particles more uniformly dispersed, but also the ether chains of cellulose ether can wrap the aerogel particles, preventing the nanopores of the aerogel from losing their excellent thermal insulation performance due to water absorption. (2) Latex powder has a film-forming and bonding effect. The polymer EVA film generated by it can not only enhance the bubble wall thickness of the foam and inhibit stress concentration, thus reducing the strength loss of the mortar, but also can interpenetrate with the molecular chains of cellulose ether to form a flexible skeleton, which plays a certain toughening effect on the thermal insulation mortar.

[0022] The thermal insulation mortar prepared according to the present invention has an ultra-low thermal conductivity (0.018-0.030 W / (m·K)) and a low density (137-160 kg / m³). 3It has good fire resistance (Class A), easy-to-control thermal insulation performance, easy molding, and simple operation. It can significantly increase the energy-saving effect of buildings and reduce carbon emissions, so it has a good application in the field of wall insulation. Attached Figure Description

[0023] Figure 1 The SEM image of the lightweight and high-efficiency thermal insulation mortar specimen provided in Embodiment 1 of the present invention is shown.

[0024] Figure 2 The SEM image of the lightweight and high-efficiency thermal insulation mortar specimen provided in Embodiment 2 of the present invention is shown.

[0025] Figure 3 The SEM image of the lightweight and high-efficiency thermal insulation mortar specimen provided in Embodiment 3 of the present invention is shown.

[0026] Figure 4 The SEM image of the lightweight and high-efficiency thermal insulation mortar specimen provided in Embodiment 4 of the present invention is shown.

[0027] Figure 5 The diagram shows the thermal conductivity of four lightweight and high-efficiency thermal insulation mortar specimens provided in Examples 1-4 of the present invention.

[0028] Figure 6 The diagram shows the dry density of four lightweight and high-efficiency thermal insulation mortar specimens provided in Examples 1-4 of the present invention.

[0029] Figure 7 The diagram shows the compressive strength of four lightweight and high-efficiency thermal insulation mortar specimens provided in Examples 1-4 of the present invention. Detailed Implementation

[0030] To better understand the above-described objects, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the present invention; however, the present invention may be practiced in other ways different from those described herein, and therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] According to one embodiment of the present invention, a lightweight and high-efficiency thermal insulation mortar is disclosed, comprising the following components by weight: 28-40 parts of cementitious material, 29-35.75 parts of water, 16-35 parts of hydrophobic aerogel particles, 5-9 parts of foam, 0.5-2 parts of water-reducing agent, 0.2-1.5 parts of cellulose ether, 0.1-0.5 parts of redispersible latex powder, and 0.2-0.7 parts of expanding agent.

[0032] In this embodiment, the cementitious material is sulfoaluminate cement or composite silicate cement, wherein the composite silicate cement comprises the following components: ordinary silicate cement, gypsum, mineral powder, and silica fume, with a mass ratio of 1:(3-5):(2-4):(0.3-1). The cellulose ether is at least one of hydroxyethyl methyl cellulose ether, hydroxymethyl cellulose ether, hydroxypropyl methyl cellulose ether, and hydroxyethyl cellulose; the redispersible latex powder is one of a copolymer of ethylene and vinyl acetate, a copolymer of vinyl acetate and ethylene tert-carbonate, and an acrylic acid copolymer; the expanding agent is selected from one of calcium sulfoaluminate expanding agents, calcium oxide expanding agents, and composite expanding agents; the water-reducing agent is selected from one of naphthalene-based high-efficiency water-reducing agents, aliphatic high-efficiency water-reducing agents, amino high-efficiency water-reducing agents, and polycarboxylate high-performance water-reducing agents.

[0033] According to the above embodiments, preferably, the aerogel particles are hydrophobic silica aerogel particles produced by supercritical drying, with a particle size of 2-4 mm and a bulk density of 0.06-0.1 g / cm³. 3 It has a porosity of 90-98%, a thermal conductivity of 0.015-0.026 W / (m·K) at an average temperature of 25℃, and its dosage is 75-95 vol of the total mortar volume.

[0034] According to the above embodiments, preferably, the foam is foam generated by physical foaming of a foaming agent through a lightweight cement foaming machine, and the foaming agent is one or more of rosin-based foaming agents, synthetic surfactant foaming agents, animal protein foaming agents, and plant protein foaming agents; the amount of foam used is 15%-24% of the mass of the cementitious material.

[0035] According to the above embodiments, preferably, the cellulose ether is hydroxypropyl methylcellulose ether.

[0036] According to the above embodiments, preferably, the redispersible latex powder is a copolymer of ethylene and vinyl acetate.

[0037] According to the above embodiments, preferably, the expanding agent is a calcium sulfoaluminate expanding agent.

[0038] According to the above embodiments, preferably, the water-reducing agent is a polycarboxylate high-performance water-reducing agent with a water reduction rate of 27% and a pH value of 6.5. It has a solids content of 30% and is used at a dosage of 1-5 wt% of the cementitious material.

[0039] According to the above embodiments, preferably, the mass ratio of cellulose ether, redispersible latex powder and swelling agent is (7-38):(2-19):(3-21).

[0040] like Figures 1 to 7As shown, according to the lightweight and high-efficiency thermal insulation mortar disclosed in the above embodiments, Examples 1-4 provide preparation methods for lightweight and high-efficiency thermal insulation mortar with different material ratios, and four kinds of lightweight and high-efficiency thermal insulation mortars were prepared. The performance of the mortar specimens was experimentally verified.

[0041] The raw materials used in the experiment were: Sulfoaluminate cement: bulk density 1.28 g / cm³ 3 .

[0042] Portland cement: Grade 42.5 ordinary Portland cement, bulk density 1.17 g / cm³ 3 .

[0043] Gypsum: Bulk density 1.23 g / cm³ 3 .

[0044] Mineral powder: bulk density 1.18 g / cm³ 3 .

[0045] Silica fume: bulk density 0.48 g / cm³ 3 .

[0046] Hydrophobic aerogel particles: Hydrophobic silica aerogel particles produced by supercritical drying method, with a particle size of 2-4 mm and a bulk density of 0.06-0.1 g / cm³. 3 It has a porosity of 90-98% and a thermal conductivity of 0.0204 W / (m·K) at an average temperature of 25℃.

[0047] Water-reducing agent: Polycarboxylate high-performance water-reducing agent.

[0048] Redispersible latex powder: a copolymer of ethylene and vinyl acetate.

[0049] Cellulose ether: Hydroxypropyl methylcellulose ether (HPMC).

[0050] The thermal conductivity of thermal insulation mortar shall be tested in accordance with GB / T 10294. 2008 Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials: Protective Hot Plate Method; The dry density test of thermal insulation mortar shall be conducted in accordance with GB / T 20473. 2021 building insulation mortar; The compressive strength test of thermal insulation mortar shall be conducted in accordance with GB / T 5486. 2008 Test Methods for Inorganic Rigid Thermal Insulation Products; The combustion performance testing of thermal insulation mortar shall be conducted in accordance with GB 8624. 2012 Classification and Testing of Combustion Performance of Building Materials and Products.

[0051] Example 1: (1) Mix 39 parts of sulfoaluminate cement, 0.8 parts of cellulose ether, 0.47 parts of redispersible latex powder and 0.28 parts of expansion agent to form a dry powder, pour it into a mortar mixing pot and stir for 1-2 minutes until the dry powder is uniform; (2) Add 1.5 parts of water-reducing agent to 35.75 parts of water and mix until uniform. Then pour the mixed liquid into the mortar mixing pot and stir until the slurry is free of lumps and dispersed. Then pour 16 parts of hydrophobic aerogel particles into the mortar mixing pot. Before the aerogel particles are completely covered by the slurry, immediately proceed to step (3). (3) The foaming agent was physically foamed using a lightweight cement foaming machine beforehand. Then, the obtained 7 parts of foam were immediately added to the mortar mixing pot and stirred until all the foam was incorporated into the mortar and no foam residue remained on the surface of the mortar, thus obtaining the product. The product was then placed in a mold and cured at room temperature and humidity (10-30℃, 50-85%RH) for 28 days to obtain thermal insulation mortar specimens. The microstructure of the specimens is as follows: Figure 1 As shown. Fire resistance rating: Class A.

[0052] like Figure 5 As shown, the lightweight and high-efficiency thermal insulation mortar prepared in Example 1 has a thermal conductivity of 0.0294 W / (m·K).

[0053] like Figure 6 As shown, the dry density of the lightweight, high-efficiency thermal insulation mortar prepared in Example 1 is 145.82 kg / m³. 3 .

[0054] like Figure 7 As shown, the compressive strength of the lightweight and high-efficiency thermal insulation mortar prepared in Example 1 is 42.1 kPa.

[0055] Example 2: (1) Mix 37 parts of sulfoaluminate cement, 0.7 parts of cellulose ether, 0.3 parts of redispersible latex powder and 0.26 parts of expansion agent to form a dry powder, pour it into a mortar mixing pot and stir for 1-2 minutes until the dry powder is uniform; (2) Add 1.3 parts of water-reducing agent to 33 parts of water and mix until uniform. Then pour the mixed liquid into the mortar mixing pot and stir until the slurry is free of lumps and dispersed. Then pour 22 parts of hydrophobic aerogel particles into the mortar mixing pot. Before the aerogel particles are completely covered by the slurry, immediately proceed to step (3). (3) The foaming agent was physically foamed using a lightweight cement foaming machine beforehand. Then, 5.5 parts of the foam were immediately added to the mortar mixing pot and stirred until all the foam was incorporated into the mortar and no foam residue remained on the surface of the mortar, thus obtaining the product. The product was then placed in a mold and cured at room temperature and humidity (10-30℃, 50-85%RH) for 28 days to obtain thermal insulation mortar specimens. The microstructure of the specimens is as follows: Figure 2 As shown. Fire resistance rating: Class A.

[0056] like Figure 5 As shown, the lightweight and high-efficiency thermal insulation mortar prepared in Example 2 has a thermal conductivity of 0.0242 W / (m·K).

[0057] like Figure 6 As shown, the dry density of the lightweight, high-efficiency thermal insulation mortar prepared in Example 2 is 153.58 kg / m³. 3 .

[0058] like Figure 7 As shown, the compressive strength of the lightweight and high-efficiency thermal insulation mortar prepared in Example 2 is 41.4 kPa.

[0059] Example 3: (1) Mix 32 parts of sulfoaluminate cement, 0.9 parts of cellulose ether, 0.2 parts of redispersible latex powder and 0.3 parts of expansion agent to form a dry powder, pour it into a mortar mixing pot and stir for 1-2 minutes until the dry powder is uniform; (2) Add 1.6 parts of water-reducing agent to 29 parts of water and mix until uniform. Then pour the mixed liquid into the mortar mixing pot and stir until the slurry is free of lumps and dispersed. Then pour 30 parts of hydrophobic aerogel particles into the mortar mixing pot. Before the aerogel particles are completely covered by the slurry, immediately proceed to step (3). (3) The foaming agent was physically foamed using a lightweight cement foaming machine beforehand. Then, the obtained 6 parts of foam were immediately added to the mortar mixing pot and stirred until all the foam was incorporated into the mortar and no foam residue remained on the surface of the mortar, thus obtaining the product. The product was then placed in a mold and cured at room temperature and humidity (10-30℃, 50-85%RH) for 28 days to obtain thermal insulation mortar specimens. The microstructure of the specimens is as follows: Figure 3 As shown. Fire resistance rating: Class A.

[0060] like Figure 5 As shown, the lightweight and high-efficiency thermal insulation mortar prepared in Example 3 has a thermal conductivity of 0.0231 W / (m·K).

[0061] like Figure 6 As shown, the dry density of the lightweight, high-efficiency thermal insulation mortar prepared in Example 3 is 137.81 kg / m³. 3 .

[0062] like Figure 7 As shown, the compressive strength of the lightweight and high-efficiency thermal insulation mortar prepared in Example 3 is 30.7 kPa.

[0063] Example 4: (1) Mix 3.5 parts silicate cement, 13.6 parts gypsum, 10.2 parts mineral powder, 1.7 parts silica fume, 0.55 parts cellulose ether, 0.17 parts redispersible latex powder and 0.2 parts expansion agent to form a dry powder, pour it into a mortar mixing pot and stir for 1-2 minutes until the dry powder is uniform; (2) Add 1.1 parts of water-reducing agent to 31.4 parts of water and mix until uniform. Then pour the mixed liquid into the mortar mixing pot and stir until the slurry is free of lumps and dispersed. Then pour 32.7 parts of hydrophobic aerogel particles into the mortar mixing pot. Before the aerogel particles are completely covered by the slurry, immediately proceed to step (3). (3) The foaming agent was physically foamed using a lightweight cement foaming machine beforehand. Then, 5.1 parts of the foam were immediately added to the mortar mixing pot and stirred until all the foam was incorporated into the mortar and no foam residue remained on the surface of the mortar, thus obtaining the product. The specimen and mold were wrapped in a full-coverage film and placed in a 60℃ oven for 7 days of heat curing. Then, the mold was removed, and the specimen was cured at room temperature and humidity (10-30℃, 50-85%RH) for 28 days. The resulting thermal insulation mortar specimen had the following microstructure: Figure 4 As shown. Fire resistance rating: Class A.

[0064] like Figure 5 As shown, the lightweight and high-efficiency thermal insulation mortar prepared in Example 4 has a thermal conductivity of 0.0187 W / (m·K).

[0065] like Figure 6 As shown, the dry density of the lightweight, high-efficiency thermal insulation mortar prepared in Example 4 is 159.84 kg / m³. 3 .

[0066] like Figure 7 As shown, the compressive strength of the lightweight and high-efficiency thermal insulation mortar prepared in Example 4 is 23.6 kPa.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lightweight and high-efficiency thermal insulation mortar, characterized in that, include: The composition, by weight, is as follows: 28-40 parts of gelling material, 29-35.75 parts of water, 16-35 parts of hydrophobic aerogel particles, 5-9 parts of foam, 0.5-2 parts of water-reducing agent, 0.2-1.5 parts of cellulose ether, 0.1-0.5 parts of redispersible latex powder, and 0.2-0.7 parts of expanding agent.

2. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The cementing material is sulfoaluminate cement or composite silicate cement, wherein the composite silicate cement includes ordinary silicate cement, gypsum, mineral powder and silica fume, and the mass ratio between the ordinary silicate cement, the gypsum, the mineral powder and the silica fume is 1:(3-5):(2-4):(0.3-1).

3. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The cellulose ether is at least one of hydroxyethyl methyl cellulose ether, hydroxymethyl cellulose ether, hydroxypropyl methyl cellulose ether, and hydroxyethyl cellulose ether.

4. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The redispersible latex powder is one of the following: a copolymer of ethylene and vinyl acetate, a copolymer of vinyl acetate and ethylene tert-carbonate, or an acrylic acid copolymer; the expanding agent is one of the following: calcium sulfoaluminate, calcium oxide, or calcium sulfoaluminate-calcium oxide.

5. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The mass ratio of the cellulose ether, the redispersible latex powder, and the swelling agent is (7-38):(2-19):(3-21).

6. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The water-reducing agent is used at a rate of 1-5 wt% of the cementitious material; the water-reducing agent is a high-performance polycarboxylate water-reducing agent with a water reduction rate of 25-35%, a pH value of 6.5, and a solid content of 20-60%.

7. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The amount of hydrophobic aerogel particles used is 75-95 vol% of the total mortar volume; the hydrophobic aerogel particles are hydrophobic silica aerogel particles produced by supercritical drying, with a particle size of 2-4 mm and a bulk density of 0.06-0.1 g / cm³. 3 It has a porosity of 90-98% and a thermal conductivity of 0.015-0.026 W / (m·K) at an average temperature of 25℃.

8. The lightweight and high-efficiency thermal insulation mortar according to claim 1, characterized in that, The amount of foam used is 15%-24wt% of the mass of the cementitious material; the foam is foam obtained by physical foaming of a foaming agent, wherein the foaming agent is one or more of rosin-based foaming agents, synthetic surfactant foaming agents, animal protein foaming agents, and plant protein foaming agents.

9. A method for preparing lightweight and high-efficiency thermal insulation mortar, characterized in that, include: Raw materials are prepared according to the material ratio of the lightweight and high-efficiency thermal insulation mortar as described in any one of claims 1 to 8, and processed through the following steps: Dry material mixing: Mix the gelling material, cellulose ether, redispersible latex powder and expansion agent evenly to obtain a dry powder; Add water-reducing agent: After adding water-reducing agent to water and stirring evenly, add the mixed liquid to the dry powder and stir until there are no lumps to obtain wet slurry; Adding aerogel particles: Add hydrophobic silica aerogel particles to the wet slurry and stir; Adding foam: Before the hydrophobic silica aerogel particles are completely coated by the slurry, add the foam generated by the foaming agent and continue stirring until there is no foam residue on the surface of the slurry, and the finished thermal insulation mortar is obtained.

10. The method for preparing lightweight and high-efficiency thermal insulation mortar according to claim 9, characterized in that, Also includes: Material molding: The finished thermal insulation mortar is poured into a mold and cured at room temperature and humidity to obtain the molded material. Room temperature and humidity refer to a temperature of 10-30℃ and a humidity of 50-85%RH. The finished thermal insulation mortar has a thermal conductivity of 0.018-0.030 W / (m·K) and a dry density of 137-160 kg / m³. 3 The compressive strength at 28 days is 23.6-42.1 kPa.

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