Novel aerogel composite geopolymer thermal insulation material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of building thermal insulation materials, in particular to a novel aerogel composite geopolymer thermal insulation material, a preparation method and application of the novel aerogel composite geopolymer thermal insulation material, and the novel aerogel composite geopolymer thermal insulation material comprises, by weight, 40-80 parts of industrial solid waste base materials; 5 to 15 parts of a geopolymer composite activator; 1 to 10 parts of aerogel; 5 to 20 parts of hollow glass beads; 1-6 parts of a modifier; and 10 to 30 parts of deionized water. According to the invention, the aerogel is utilized to construct a nano-scale thermal insulation barrier, meanwhile, a micron-scale supporting framework is formed by virtue of the hollow glass beads, and interface modification is carried out by virtue of the silane coupling agent, so that the problems that the light filler and a geopolymer matrix are poor in binding property and easy to agglomerate are effectively solved, and synergistic improvement of thermal insulation performance and mechanical strength is realized. The dry density of the material is remarkably reduced, the water absorption rate is low, the weather resistance is excellent, and the double requirements of ultra-low energy consumption buildings and low-temperature industrial equipment for efficient heat preservation and structural stability are met.

Description

Technical Field

[0001] This application relates to the field of building insulation materials technology, and in particular to a novel aerogel composite geopolymer insulation material, its preparation method and application. Background Technology

[0002] The construction, industrial, and new energy sectors have placed dual demands on insulation materials, requiring both ultra-low thermal conductivity and high stability. Traditional geopolymer materials, made from industrial solid waste, possess advantages such as environmental friendliness, high-temperature resistance, and good mechanical properties. However, due to their predominantly macroporous pore structure, their thermal conductivity is typically higher than 0.06 W / (m·K), making it difficult to meet the needs of high-end insulation applications. If only a single lightweight component (such as hollow glass microspheres) is used for modification, poor interfacial bonding can easily lead to a significant decrease in compressive strength (often below 2.0 MPa), with limited improvement in insulation performance.

[0003] Existing technology 1, CN115215678A, proposes an aerogel-geopolymer composite material with a thermal conductivity reduced to 0.035 W / (m·K). However, this material uses pure fly ash as a base material, resulting in low early strength (7-day compressive strength of only 1.8 MPa), and the aerogel is prone to agglomeration, leading to uneven thermal insulation performance. Existing technology 2, CN114853291B, uses hollow glass microspheres to modify the geopolymer, increasing the compressive strength to 2.5 MPa, but the thermal conductivity is still higher than 0.040 W / (m·K), which cannot meet the insulation requirements of ultra-low energy consumption buildings and low-temperature industrial equipment. Summary of the Invention

[0004] This application provides a novel aerogel composite geopolymer thermal insulation material, its preparation method, and its application, in order to solve the problems in the prior art that it is difficult to achieve ultra-low thermal conductivity while maintaining sufficient mechanical strength, and that often face problems such as poor component interface bonding, uneven performance, and insufficient adaptability to low-temperature environments.

[0005] This application provides a novel aerogel composite geopolymer insulation material, wherein the composite geopolymer insulation material is composed of the following parts by weight: Industrial solid waste base material: 40-80 parts; Geopolymer composite activator: 5-15 parts; Aerogel: 1-10 parts; Hollow glass microspheres: 5-20 parts; Modifier: 1-6 parts; Deionized water: 10-30 parts.

[0006] The composite geopolymer insulation material is composed of the following parts by weight: Industrial solid waste base material: 50-70 parts; Geopolymer composite activator: 6-10 parts; Aerogel: 3-8 parts; Hollow glass microspheres: 8-15 parts; Modifier: 2-5 parts; Deionized water: 15-22 parts.

[0007] The industrial solid waste base material is a mixture of fly ash and slag in a mass ratio of (2:1) to (3:1).

[0008] The aerogel is a hydrophobic silica aerogel with a particle size of 5-20 μm and a specific surface area ≥600 m². 2 / g, porosity ≥90%.

[0009] The hollow glass microspheres are of high silica-oxygen type, with a particle size of 50-150μm, a compressive strength ≥10MPa, and a thermal conductivity ≤0.025W / (m・K).

[0010] The geopolymer composite activator is composed of sodium hydroxide, water glass and calcium hydroxide, with a molar ratio of (3:1:0.2) to (3:1:0.4).

[0011] The water glass has a modulus of 1.9-2.3 and a Baume degree of 39-43Be′.

[0012] The modifier is a mixture of silane coupling agent KH-560 and nano calcium carbonate in a mass ratio of (1:2) to (1:4).

[0013] This application also proposes a method for preparing a novel aerogel composite geopolymer thermal insulation material, comprising the following steps: S1. Raw material pretreatment: Fly ash and slag are crushed to a particle size ≤0.075mm and dried at 100-105℃ for 5-7h to remove free moisture; hollow glass microspheres are placed in an oven at 120-130℃ for 1.5-2.5h, cooled and mixed with aerogel, sprayed with 0.5%-1% KH-560 ethanol solution, stirred for 15-20min, and allowed to stand for 30-40min to complete surface modification, ready for use; S2. Preparation of activator: Dissolve sodium hydroxide in water according to the proportion, stir until completely dissolved and cool to 25-30℃, add water glass and calcium hydroxide, stir at 400-500r / min for 40-50min to obtain a uniform geopolymer composite activator solution. S3. Slurry preparation: Add the pretreated industrial solid waste base material and nano-calcium carbonate to a planetary mixer and stir at a low speed of 250-350 r / min for 6-8 min. Then, slowly add the geopolymer composite activator solution at a rate of 10-15 mL / min. Heat the mixture to 40-45℃ and stir at a high speed of 800-1000 r / min for 12-15 min. Finally, add the surface-modified aerogel-hollow glass microsphere mixture and stir at a medium speed of 500-600 r / min for 4-6 min to form a slurry with no agglomeration and good fluidity. S4. Molding and Curing: Inject the slurry into the pre-set mold and let it stand for 8-10 hours in an environment of 30-35℃ and relative humidity ≥85%. The mold is covered with polyethylene film. During this period, gently tap the side wall of the mold to release air every 2 hours. After demolding, place it in a saturated steam curing chamber at 70-80℃ and steam pressure of 0.12-0.18MPa for 10-14 hours, and then transfer it to the natural environment for curing for 8-12 days to obtain a new type of aerogel composite geopolymer thermal insulation material.

[0014] This application also proposes an application of a novel aerogel composite geopolymer insulation material. The composite geopolymer insulation material can be used in ultra-thin insulation systems for building exterior walls. It is cut into boards with a thickness of 20-40mm and bonded to the wall base layer with polymer-modified adhesive mortar. The anchor spacing is 350-450mm, and the surface layer is protected with crack-resistant mortar, alkali-resistant fiberglass mesh, and elastic putty. Alternatively, it can be used for thermal insulation of industrial low-temperature equipment. It is processed into arc-shaped or irregular-shaped components, spliced ​​and wrapped with low-temperature adhesive, and the outer layer is provided with a polyurethane moisture-proof layer and a stainless steel protective shell.

[0015] Therefore, this application has at least the following beneficial effects: (1) The embodiments of this application achieve a leapfrog improvement in thermal insulation performance through the "nano-micro" multi-level thermal insulation structure design. Among them, the hydrophobic silica aerogel effectively restricts the free flow of air molecules with its nano-sized pores, thereby significantly inhibiting convective heat transfer and solid heat conduction; the high silica hollow glass microspheres fill the gaps of the aerogel with their micron-sized closed pores, further blocking the heat transfer path. The two work together to form a continuous thermal insulation barrier, which makes the thermal insulation efficiency of the material more than 50% higher than that of traditional geopolymer materials; the three-dimensional network structure (containing Si-O-Al-O bonds) formed by the geopolymer matrix under the action of alkaline activator provides a stable skeleton support for this multi-level thermal insulation structure. (2) In addition, the hydrophobic aerogel and KH-560 modification give the material a low water absorption rate, which can avoid the decay of thermal insulation performance in humid environments; the high temperature stability of the geopolymer gel and the impact resistance of the hollow glass microspheres make it suitable for complex scenarios such as high-temperature industrial equipment and outdoor building exterior walls. In terms of application form, it can be cut into 20-40mm ultra-thin plates for building exterior wall insulation (reducing the space occupied by the wall), or it can be processed into arc-shaped and irregular-shaped components for thermal insulation of industrial low-temperature equipment. With the polyurethane moisture-proof layer and stainless steel protective shell, it can meet the thermal insulation requirements in the temperature range of -40℃ to 300℃; (3) In the embodiments of this application, fly ash and slag undergo a “silica-alumina-calcium” synergistic reaction under the action of a composite activator to generate a dense geopolymer gel network (mainly forming ≡Si-O-Al-O≡ bonds), providing basic mechanical support for the material; the epoxy groups of the silane coupling agent KH-560 can react with the hydroxyl groups (-OH) in the geopolymer gel and the groups on the surface of aerogel and hollow glass microspheres to form strong chemical bonds (such as Si-O-Si bonds), constructing an “organic-inorganic transition layer”, which significantly improves the interfacial bonding force and avoids the strength loss caused by poor interfacial bonding. Nano-calcium carbonate (particle size ≤50nm) can effectively fill the micropores of the geopolymer gel, further improving the density and strength of the material; (4) The embodiments of this application use industrial solid waste as the main raw material, with a utilization rate of 50%-70%. This not only realizes the resource utilization of solid waste and reduces stockpiling pollution, but also reduces the cost of raw materials. The preparation process does not require high-temperature calcination. Through room temperature stirring and medium-low temperature curing, energy consumption is reduced by 30%-40% compared with traditional aerogel composite materials, and carbon emissions are reduced by more than 40% compared with cement-based insulation materials. At the same time, the bulk density of the material is ≤0.8g / cm³. 3 Compared with traditional geopolymers, it reduces weight by 30%-40%, which can reduce building structural load, reduce transportation and construction costs, and has significant economic benefits throughout its entire life cycle; (5) In the raw material pretreatment stage of this application, the problems of aerogel agglomeration and interface bonding are solved by preheating and surface modification; the slurry preparation adopts a staged stirring of "low-speed dispersion-high-speed reaction-medium-speed compounding", which not only ensures uniform mixing of components, but also avoids aerogel breakage and hollow glass microsphere deformation; the molding and curing are shortened by static venting and saturated steam curing, and the subsequent natural curing further optimizes the performance without the need for complex equipment. The whole process is simple and controllable, with a short production cycle and no harmful gas emissions. It can be mass-produced by modifying existing geopolymer material production lines.

[0016] This solves the problems in existing technologies that make it difficult to achieve ultra-low thermal conductivity while maintaining sufficient mechanical strength, and often face issues such as poor component interface bonding, uneven performance, and insufficient adaptability to low-temperature environments.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart illustrating the preparation method of the novel aerogel composite geopolymer thermal insulation material according to the embodiments of this application; Figure 2 This is a structural diagram of an industrial equipment application provided according to an embodiment of this application; Figure 3 This is a structural diagram of an application for building exterior walls provided according to an embodiment of this application; Figure 4 A scanning electron microscope image of the novel aerogel composite geopolymer thermal insulation material provided in Embodiment 1 of this application; Figure 5 A scanning electron microscope image of the novel aerogel composite geopolymer thermal insulation material provided according to Embodiment 2 of this application; Figure 6 This is a scanning electron microscope image of the novel aerogel composite geopolymer thermal insulation material provided according to Embodiment 3 of this application. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] In the embodiments of this application, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0021] The present application will now be described with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present application in any way.

[0022] Example 1 This application provides a novel aerogel composite geopolymer insulation material, which is composed of the following parts by weight: Industrial solid waste base material: 50 parts; Geopolymer composite activator: 6 parts; Aerogel: 3 parts; Hollow glass microspheres: 8 parts; Modifier: 2 parts; Deionized water: 15 parts.

[0023] The industrial solid waste base material is a mixture of fly ash and slag at a mass ratio of 2:1.

[0024] The aerogel is a hydrophobic silica aerogel with a particle size of 5-20 μm and a specific surface area of ​​≥600 m². 2 / g, porosity ≥90%.

[0025] Among them, the hollow glass microspheres are of high silica-oxygen type, with a particle size of 50-150μm, a compressive strength ≥10MPa, and a thermal conductivity ≤0.025W / (m・K).

[0026] The geopolymer composite activator is composed of sodium hydroxide, water glass and calcium hydroxide, with a molar ratio of 3:1:0.2.

[0027] The water glass has a modulus of 1.9 and a Baumé degree of 39Be′.

[0028] The modifier is a mixture of silane coupling agent KH-560 and nano-calcium carbonate at a mass ratio of 1:2.

[0029] This application also proposes a method for preparing a novel aerogel composite geopolymer thermal insulation material, such as... Figure 1 As shown, it includes the following steps: S1. Raw material pretreatment: Fly ash and slag are crushed to a particle size ≤0.075mm and dried at 100℃ for 5h to remove free moisture; hollow glass microspheres are placed in a 120℃ oven for 1.5h preheating, cooled and mixed with aerogel, sprayed with a modifier with a mass fraction of 0.5%, stirred for 15min, and allowed to stand for 30min to complete the surface modification, ready for use; It is understood that the embodiments of this application use fly ash and slag as a base material, and through the synergistic reaction of "silica-alumina-calcium", a dense and stable geopolymer gel network is formed, which provides basic mechanical support for the material. The epoxy groups of KH-560 can react with the hydroxyl groups in the geopolymer gel to enhance the interfacial adhesion between the thermal insulation component and the matrix; the nano-calcium carbonate particles with a diameter of ≤50nm can fill the micropores of the geopolymer gel, improving the material density and compressive strength. The combination of the two can simultaneously optimize the interfacial and mechanical properties of the material.

[0030] It should be noted that preheating of hollow glass microspheres can remove surface adsorbed water and avoid fluctuations in slurry moisture content; after mixing aerogel and hollow glass microspheres, modification with KH-560 ethanol solution can form an organic-inorganic transition layer on the surface of the components, solving the problem of aerogel agglomeration and improving compatibility with geopolymer gel.

[0031] S2. Preparation of activator: Dissolve sodium hydroxide in deionized water according to the proportion, stir until completely dissolved and cool to 25°C, add water glass and calcium hydroxide, stir at 400 r / min for 40 min to obtain a uniform geopolymer composite activator solution. It is understood that in the composite activator of this application embodiment, sodium hydroxide provides a strongly alkaline environment to promote the dissolution of active ingredients, water glass supplements the silicon source to optimize the gel structure, and calcium hydroxide regulates the reaction rate to prevent the slurry from coagulating too quickly, thus balancing reaction efficiency and gel density.

[0032] S3. Slurry preparation: The pretreated industrial solid waste base material and nano calcium carbonate were added to a planetary mixer and stirred at a low speed of 250 r / min for 6 min. Then, the geopolymer composite activator solution was slowly added dropwise at a rate of 10 mL / min. The temperature was raised to 40℃ and stirred at a high speed of 800 r / min for 12 min. Finally, the surface-modified aerogel-hollow glass microsphere mixture was added and stirred at a medium speed of 500 r / min for 4 min to form a slurry with no agglomeration and good fluidity. It is understood that the hydrophobic silica aerogel in this embodiment has a nanoscale porous structure with a porosity ≥90%, which can effectively block heat conduction, but its mechanical strength is low and it is prone to agglomeration. The high-silica hollow glass microspheres have a micron-scale closed pore structure with a compressive strength ≥10MPa, which can fill the gaps in the aerogel and enhance the overall strength of the material. When the two are used together, the aerogel constructs a nanoscale thermal insulation barrier, and the hollow glass microspheres construct a micron-scale support-thermal insulation structure, forming a "nano-micro" multi-level thermal insulation system, which significantly reduces the thermal conductivity. At the same time, the interfacial bonding force between the two and the geopolymer gel can be improved by modifying with the silane coupling agent KH-560, avoiding component shedding or agglomeration.

[0033] It should be noted that a staged stirring strategy of "low-speed mixing - high-speed reaction with heating - medium-speed compounding" is adopted. Low-speed stirring ensures uniform dispersion of the base material and modifier, high-speed stirring with heating (40-45℃) promotes full reaction of the geopolymer, and medium-speed stirring adds heat-insulating components to avoid aerogel breakage and deformation of hollow glass microspheres, thus ensuring the uniformity of the slurry.

[0034] S4. Molding and Curing: The slurry is injected into a pre-set mold and left to stand for 8 hours at 30℃ and relative humidity ≥85%. The mold is covered with polyethylene film. During this period, the side wall of the mold is gently tapped every 2 hours to release air. After demolding, it is placed in a saturated steam curing chamber at 70℃ and steam pressure 0.12MPa for 10 hours, and then transferred to a natural environment for curing for 8 days to obtain a new type of aerogel composite geopolymer thermal insulation material.

[0035] It is understood that the embodiments of this application shorten the early strength formation time through static venting and saturated steam curing, and the subsequent natural curing further optimizes the performance. No complex equipment is required, and mass production can be achieved by modifying existing geopolymer material production lines.

[0036] It should be noted that tapping the mold to release air during static setting can reduce internal air bubble defects. Saturated steam curing (70-80℃, 0.12-0.18MPa) can accelerate the curing of the geopolymer gel and improve early strength. Subsequent natural curing can further optimize the gel structure and ensure long-term stability of material performance.

[0037] This application also proposes an application of a novel aerogel composite geopolymer thermal insulation material, such as... Figure 2 As shown, composite geopolymer insulation material can be used in ultra-thin exterior wall insulation systems. It is cut into 20mm thick boards and bonded to the wall substrate using polymer-modified adhesive mortar. Anchor spacing is 350mm. The surface layer uses crack-resistant mortar combined with alkali-resistant fiberglass mesh and elastic putty for protection. Figure 3 As shown, it can also be used for thermal insulation of industrial cryogenic equipment. It is processed into arc-shaped or irregular-shaped components, spliced ​​and wrapped with cryogenic adhesive, and the outer layer is set with a polyurethane moisture-proof layer and a stainless steel protective shell.

[0038] Example 2 This application provides a novel aerogel composite geopolymer insulation material, which is composed of the following parts by weight: Industrial solid waste base material: 60 parts; Geopolymer composite activator: 8 parts; Aerogel: 5 parts; Hollow glass microspheres: 10 parts; Modifier: 3 parts; Deionized water: 20 parts.

[0039] The industrial solid waste base material is a mixture of fly ash and slag at a mass ratio of 3:1.

[0040] The aerogel is a hydrophobic silica aerogel with a particle size of 5-20 μm and a specific surface area of ​​≥600 m². 2 / g, porosity ≥90%.

[0041] Among them, the hollow glass microspheres are of high silica-oxygen type, with a particle size of 50-150μm, a compressive strength ≥10MPa, and a thermal conductivity ≤0.025W / (m・K).

[0042] The geopolymer composite activator is composed of sodium hydroxide, water glass and calcium hydroxide, with a molar ratio of 3:1:0.4.

[0043] The water glass has a modulus of 2.0 and a Baumé degree of 40Be′.

[0044] The modifier is a mixture of silane coupling agent KH-560 and nano-calcium carbonate at a mass ratio of 1:3.

[0045] This application also proposes a method for preparing a novel aerogel composite geopolymer thermal insulation material, such as... Figure 1 As shown, it includes the following steps: S1. Raw material pretreatment: Fly ash and slag are crushed to a particle size ≤0.075mm and dried at 100-105℃ for 6h to remove free moisture; hollow glass microspheres are preheated in an oven at 125℃ for 2.0h, cooled and mixed with aerogel, sprayed with a modifier with a mass fraction of 0.8, stirred for 17min, and allowed to stand for 35min to complete the surface modification, ready for use; S2. Preparation of activator: Dissolve sodium hydroxide in deionized water according to the proportion, stir until completely dissolved and cool to 28°C, add water glass and calcium hydroxide, stir at 450 r / min for 45 min to obtain a uniform geopolymer composite activator solution. S3. Slurry preparation: The pretreated industrial solid waste base material and nano calcium carbonate were added to a planetary mixer and stirred at a low speed of 300 r / min for 7 min. Then, the geopolymer composite activator solution was slowly added dropwise at a rate of 12 mL / min. The temperature was raised to 43℃ and stirred at a high speed of 900 r / min for 14 min. Finally, the surface-modified aerogel-hollow glass microsphere mixture was added and stirred at a medium speed of 550 r / min for 5 min to form a slurry with no agglomeration and good fluidity. S4. Molding and Curing: The slurry is injected into a pre-set mold and left to stand for 9 hours at 34℃ and relative humidity ≥85%. The mold is covered with polyethylene film. During this period, the side wall of the mold is gently tapped every 2 hours to release air. After demolding, it is placed in a saturated steam curing chamber at 75℃ and steam pressure 0.15MPa for 12 hours, and then transferred to a natural environment for curing for 10 days to obtain a new type of aerogel composite geopolymer thermal insulation material.

[0046] This application also proposes an application of a novel aerogel composite geopolymer thermal insulation material, such as... Figure 2 As shown, composite geopolymer insulation material can be used in ultra-thin exterior wall insulation systems. It is cut into 30mm thick boards and bonded to the wall substrate using polymer-modified adhesive mortar. Anchor spacing is 400mm. The surface layer uses crack-resistant mortar combined with alkali-resistant fiberglass mesh and elastic putty for protection. Figure 3 As shown, it can also be used for thermal insulation of industrial cryogenic equipment. It is processed into arc-shaped or irregular-shaped components, spliced ​​and wrapped with cryogenic adhesive, and the outer layer is set with a polyurethane moisture-proof layer and a stainless steel protective shell.

[0047] Example 3 This application provides a novel aerogel composite geopolymer insulation material, which is composed of the following parts by weight: Industrial solid waste base material: 70 parts; Geopolymer composite activator: 10 parts; Aerogel: 8 parts; Hollow glass microspheres: 15 parts; Modifier: 5 parts; Deionized water: 22 parts.

[0048] The industrial solid waste base material is a mixture of fly ash and slag at a mass ratio of 3:1.

[0049] The aerogel is a hydrophobic silica aerogel with a particle size of 5-20 μm and a specific surface area of ​​≥600 m². 2 / g, porosity ≥90%.

[0050] Among them, the hollow glass microspheres are of high silica-oxygen type, with a particle size of 50-150μm, a compressive strength ≥10MPa, and a thermal conductivity ≤0.025W / (m・K).

[0051] The geopolymer composite activator is composed of sodium hydroxide, water glass and calcium hydroxide, with a molar ratio of 3:1:0.4.

[0052] The water glass has a modulus of 2.3 and a Baumé degree of 43Be′.

[0053] The modifier is a mixture of silane coupling agent KH-560 and nano-calcium carbonate at a mass ratio of 1:4.

[0054] This application also proposes a method for preparing a novel aerogel composite geopolymer thermal insulation material, such as... Figure 1 As shown, it includes the following steps: S1. Raw material pretreatment: Fly ash and slag are crushed to a particle size ≤0.075mm and dried at 105℃ for 7h to remove free moisture; hollow glass microspheres are preheated in an oven at 130℃ for 2.5h, cooled and mixed with aerogel, sprayed with a modifier of 1% by mass, stirred for 20min, and allowed to stand for 40min to complete surface modification, ready for use; S2. Preparation of activator: Dissolve sodium hydroxide in deionized water according to the proportion, stir until completely dissolved and cool to 30°C, add water glass and calcium hydroxide, stir at 500 r / min for 50 min to obtain a uniform geopolymer composite activator solution. S3. Slurry preparation: The pretreated industrial solid waste base material and nano calcium carbonate are added to a planetary mixer and stirred at a low speed of 350 r / min for 8 min. Then, the geopolymer composite activator solution is slowly added dropwise at a rate of 15 mL / min. The temperature is raised to 45℃ and stirred at a high speed of 1000 r / min for 15 min. Finally, the surface-modified aerogel-hollow glass microsphere mixture is added and stirred at a medium speed of 600 r / min for 6 min to form a slurry with no agglomeration and good fluidity. S4. Molding and Curing: The slurry is injected into a pre-set mold and left to stand for 10 hours at 35℃ and relative humidity ≥85%. The mold is covered with polyethylene film. During this period, the side wall of the mold is gently tapped every 2 hours to release air. After demolding, it is placed in a saturated steam curing chamber at 80℃ and steam pressure 0.18MPa for 14 hours, and then transferred to a natural environment for 12 days to obtain a new type of aerogel composite geopolymer thermal insulation material.

[0055] This application also proposes an application of a novel aerogel composite geopolymer thermal insulation material, such as... Figure 2 As shown, composite geopolymer insulation material can be used in ultra-thin exterior wall insulation systems. It is cut into 40mm thick boards and bonded to the wall substrate using polymer-modified adhesive mortar. Anchor spacing is 450mm. The surface layer uses crack-resistant mortar combined with alkali-resistant fiberglass mesh and elastic putty for protection. Figure 3 As shown, it can also be used for thermal insulation of industrial cryogenic equipment. It is processed into arc-shaped or irregular-shaped components, spliced ​​and wrapped with cryogenic adhesive, and the outer layer is set with a polyurethane moisture-proof layer and a stainless steel protective shell.

[0056] Comparative Example 1 This comparative example provides a novel aerogel composite geopolymer thermal insulation material, which differs from Example 1 only in that it does not contain aerogel and hollow glass microspheres; the remaining components and processes are exactly the same as in Example 1.

[0057] Comparative Example 2 This comparative example provides a novel aerogel composite geopolymer thermal insulation material, which differs from Example 1 only in that it does not contain a geopolymer composite activator; the remaining components and processes are exactly the same as in Example 1.

[0058] Comparative Example 3 This comparative example provides a novel aerogel composite geopolymer thermal insulation material, which differs from Example 1 only in that it does not contain aerogel, hollow glass microspheres, or geopolymer composite activator; the remaining components and processes are exactly the same as in Example 1.

[0059] Performance testing The novel aerogel composite geopolymer thermal insulation materials prepared in Examples 1-3 and Comparative Examples 1-3 were analyzed according to GB / T5486-2008 "Test Methods for Inorganic Rigid Thermal Insulation Products". The performance test results are shown in Table 1 below.

[0060] Table 1 Performance Tests of Novel Aerogel Composite Geopolymer Insulation Materials

[0061] like Figure 4 , Figure 5 , Figure 6 As shown in Table 1, the novel aerogel composite geopolymer thermal insulation materials prepared in Examples 1-3 of this invention exhibit a clear and convincing contrast with the comparative examples in terms of key properties such as thermal conductivity, compressive strength, bulk density, and water absorption, fully demonstrating the technical advantages of this invention.

[0062] Performance comparison analysis shows that the material of this invention possesses excellent thermal insulation performance. The thermal conductivity of Examples 1-3 is in the range of 0.024~0.028 W / (m·K), which is significantly lower than that of Comparative Example 1 (0.068 W / (m·K). This result proves that the introduction and synergistic effect of aerogel and hollow glass microspheres are the key to endowing the material with ultra-low thermal conductivity, achieving a qualitative leap in thermal insulation performance.

[0063] Compared to the comparative examples, the material of this invention exhibits an excellent balance of comprehensive performance, successfully resolving the contradiction between "thermal insulation" and "strength" in high-performance thermal insulation materials. Compared to Comparative Example 1 (without thermal insulation components), this invention reduces the thermal conductivity by approximately 65% ​​while maintaining a practically valuable compressive strength (≥4.2 MPa) and achieves significant weight reduction (density reduction of approximately 21%). Compared to Comparative Examples 2 and 3 (without geopolymer composite activator), this invention, by forming a complete geopolymer gel network, achieves a significant increase in compressive strength (approximately 50%-160%) and a significant reduction in water absorption (approximately 70%) at similar densities, demonstrating that the geopolymer structure is the foundation for materials to achieve good mechanical properties and durability.

[0064] Comparative Example 3 (without activator or insulating component) exhibited the worst overall performance, which demonstrates the synergistic and non-obvious nature of the technical solution of this invention. The results indicate that the superior performance of this invention is not a simple summation of the components, but rather relies on the combination of a "geopolymer gel network as a supporting framework" and a "multi-level insulating system constructed from aerogel-hollow glass microspheres," enabling the material to simultaneously possess excellent comprehensive properties such as ultra-low thermal conductivity, moderate strength, low density, and low water absorption.

[0065] In summary, the embodiments of this application achieve ultra-low thermal conductivity using a multi-level thermal insulation structure (hydrophobic silica aerogel + high-silica hollow glass microspheres) from the nano to the micrometer level. Combined with the three-dimensional network support of the geopolymer matrix, the thermal insulation efficiency is improved by more than 50% compared to traditional geopolymers. Furthermore, it is adaptable to a wide temperature range of -40℃ to 300℃ and can be processed into ultra-thin or irregularly shaped components to meet different scenarios. In terms of mechanical and interface optimization, a dense gel network is formed by the synergistic reaction of fly ash and slag ("silica-alumina-calcareous"), combined with KH-560 to construct an "organic..." - The "inorganic transition layer" and nano-calcium carbonate micropore filling ensure sufficient mechanical strength and improve interfacial bonding; in terms of green economy, it uses industrial solid waste with a utilization rate of 50%-70% as raw material, and the preparation does not require high-temperature roasting, which significantly reduces energy consumption and carbon emissions, and the lightweight material reduces building load and cost; in terms of process, through staged pretreatment, stirring and curing, the process is controllable and the cycle is short, and it can be mass-produced based on existing production lines, ultimately overcoming the problems of "difficulty in balancing high mechanical strength and ultra-low thermal conductivity" as well as poor component interface and insufficient environmental adaptability.

[0066] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

[0067] The present application and its embodiments have been described above. This description is not restrictive, and the actual application is not limited thereto. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of this application, such design should fall within the protection scope of this application.

Claims

1. A novel aerogel composite geopolymer thermal insulation material, characterized in that, The composite geopolymer thermal insulation material is composed of the following components in parts by weight: industrial solid waste base material: 40-80 parts; geopolymer composite activator: 5-15 parts; aerogel: 1-10 parts; hollow glass microbeads: 5-20 parts; modifier: 1-6 parts; deionized water: 10-30 parts.

2. The aerogel composite geopolymer thermal insulation material of claim 1, wherein, The composite geopolymer thermal insulation material is composed of the following components in parts by weight: industrial solid waste base material: 50-70 parts; geopolymer composite activator: 6-10 parts; aerogel: 3-8 parts; hollow glass microbeads: 8-15 parts; modifier: 2-5 parts; deionized water: 15-22 parts.

3. The aerogel composite geopolymer thermal insulation material of claim 2, wherein, The industrial solid waste base material is a mixture of fly ash and slag in a mass ratio of (2:1) to (3:1).

4. The aerogel composite geopolymer thermal insulation material of claim 2, wherein, The aerogel is a hydrophobic silica aerogel with a particle size of 5-20 μm, a specific surface area of ≥600 m 2 / g, and a porosity of ≥90%.

5. The aerogel composite geopolymer thermal insulation material of claim 2, wherein, The hollow glass microbeads are high-silica type, with a particle size of 50-150 μm, a compressive strength of ≥10 MPa, and a thermal conductivity of ≤0.025 W / (m·K).

6. The aerogel composite geopolymer insulating material of claim 2, wherein, The geopolymer composite activator is composed of sodium hydroxide, water glass, and calcium hydroxide, with a molar ratio of (3:1:0.2) to (3:1:0.4).

7. The aerogel composite geopolymer thermal insulation material of claim 6, wherein, The water glass has a modulus of 1.9-2.3 and a Baume degree of 39-43 Be′.

8. The aerogel composite geopolymer thermal insulation material according to claim 2, wherein, The modifier is a mixture of silane coupling agent KH-560 and nano calcium carbonate in a mass ratio of (1:2) to (1:4).

9. A method for the production of the novel aerogel composite geopolymer thermal insulation material according to any one of claims 1 to 8, characterized in that, The method comprises the following steps: S1. Raw material pretreatment: grind the fly ash and slag separately to a particle size of ≤0.075 mm, and dry at 100-105 ℃ for 5-7 h to remove free water; preheat the hollow glass microbeads in an oven at 120-130 ℃ for 1.5-2.5 h, and after cooling, mix with the aerogel, spray a 0.5%-1% KH-560 ethanol solution, stir for 15-20 min, and stand for 30-40 min to complete the surface modification, and reserve; S2. Activator preparation: dissolve sodium hydroxide in water according to the proportion, stir until completely dissolved, and cool to 25-30 ℃, add water glass and calcium hydroxide, and stir at a speed of 400-500 r / min for 40-50 min to prepare a uniform geopolymer composite activator solution; S3. Slurry preparation: add the pretreated industrial solid waste base material and nano calcium carbonate to a planetary mixer, stir at a low speed of 250-350 r / min for 6-8 min, then slowly add the geopolymer composite activator solution, with a drop rate of 10-15 mL / min, heat to 40-45 ℃, and stir at a high speed of 800-1000 r / min for 12-15 min, finally add the surface-modified aerogel-hollow glass microbead mixture, and stir at a medium speed of 500-600 r / min for 4-6 min to form a slurry with good flowability and no agglomeration; S4. Molding and curing: The slurry is injected into a pre-set mold, and is left to stand for 8-10 h in an environment with a temperature of 30-35 DEG C and a relative humidity of greater than or equal to 85%, the mold is covered with a polyethylene film, and the side wall of the mold is gently tapped every 2 h to exhaust air; after demolding, the product is placed in a saturated steam curing box with a temperature of 70-80 DEG C and a steam pressure of 0.12-0.18 MPa for curing for 10-14 h, and is then transferred to a natural environment for curing for 8-12 d, to obtain a new aerogel composite geopolymer thermal insulation material.

10. Use of the novel aerogel composite geopolymer thermal insulation material according to any one of claims 1 to 8, characterized in that, The composite geopolymer thermal insulation material can be used in a building outer wall ultra-thin thermal insulation system, is cut into a plate with a thickness of 20-40 mm, is pasted to a wall base layer through a polymer modified bonding mortar, the spacing between anchor members is 350-450 mm, a surface layer is protected by using a crack-resistant mortar and an alkali-resistant glass fiber mesh cloth and an elastic putty; or is used in industrial low-temperature equipment insulation, is processed into an arc-shaped or special-shaped member, is spliced and wrapped through a low-temperature bonding agent, and a polyurethane moisture-proof layer and a stainless steel protective shell are arranged on the outer layer.

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