Novel light heat insulation building material and manufacturing method thereof

Abstract

The invention relates to the technical field of building materials, and discloses a novel light heat insulation building material and a manufacturing method thereof. 1-5 parts of a foaming agent; 3-8 parts of nano silicon dioxide; 0.5 to 3 parts of graphene oxide; 0.1 to 1 part of a carbon nanotube; 0.2 to 1 part of a silane coupling agent; 0.5-3 parts of a fiber reinforced material; 0.2 to 1 part of a super-hydrophobic coating material; and 3-7 parts of other auxiliary components, wherein the auxiliary components are selected from one or more of a dispersing agent, a coagulation accelerator, a retarder, a bonding enhancer, a defoaming agent, a pH regulator, a surfactant and a moisture-proof agent. Unification of light weight, high strength and efficient heat insulation is achieved through the collaborative design of nano-particle directional dispersion and multistage pores, improvement of long-acting water resistance and crack resistance is achieved through chemical bonding deposition of the super-hydrophobic coating, and balance of structural stability and production energy consumption is achieved through a step-by-step temperature control curing and low-temperature sintering process.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to a novel lightweight heat-insulating building material and a manufacturing method thereof. Background Art

[0002] In the field of building energy conservation, lightweight insulation materials are the core functional components for reducing energy consumption. Traditional solutions such as foamed cement and aerated concrete achieve lightweighting by introducing physical foaming agents or low-density fillers, and use surface waterproof coatings to improve weather resistance. However, the comprehensive performance of such materials in complex environments is still difficult to meet the requirements of high efficiency, energy saving and long life.

[0003] Existing technologies generally use a single foaming process combined with a silicate matrix. The uneven dispersion of the foaming agent leads to a coarse pore structure, and heat is quickly transferred through air convection in the pores, resulting in a high thermal conductivity. To make up for the strength deficiency, some technologies add low-density fillers such as expanded perlite, but this further reduces the compressive strength. Waterproofness relies on silicone spraying, and there is only physical adhesion between the coating and the substrate. It is easy to peel off in a hot and humid environment, and the water absorption rate is increased. Nano-enhancement technology attempts to introduce silica or carbon nanotubes, but insufficient mechanical stirring and dispersion causes particle agglomeration, which cannot effectively block the heat conduction path. In addition, traditional sintering requires high temperatures to ensure strength, resulting in pore collapse and a decrease in closed porosity. Although the low-temperature curing solution is energy-saving, it requires an extremely long cycle, making it difficult to balance efficiency and performance. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides a novel lightweight heat-insulating building material and a method for manufacturing the same, which solves the problem in the prior art that it is difficult to balance lightness, heat insulation, waterproofness and mechanical strength.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a new lightweight thermal insulation building material and a manufacturing method thereof, comprising: 50-60 parts of cement-based materials; 1-5 parts of foaming agent; 3-8 parts of nano silicon dioxide; 0.5-3 parts of graphene oxide; 0.1-1 part of carbon nanotubes; Silane coupling agent 0.2-1 part; Fiber reinforcement material 0.5-3 parts; 0.2-1 part of super hydrophobic coating material; 3-7 parts of other auxiliary ingredients, wherein the auxiliary ingredients are selected from one or more of dispersants, accelerators, retarders, adhesion enhancers, defoamers, pH regulators, surfactants, and moisture-proofing agents; 15-30 parts of water.

[0006] Preferably, the cement-based material is portland cement, alumina cement or a mixture thereof.

[0007] Preferably, the foaming agent is selected from hydrogen peroxide, aluminum powder or silicon carbide micropowder, and the dispersant is selected from polycarboxylate water reducer, polyvinyl alcohol or sodium dodecyl sulfate.

[0008] Preferably, the fiber reinforcement material is selected from polyvinyl alcohol fiber, basalt fiber or a combination thereof, the moisture-proof agent is selected from silane, silicone emulsion or fluoride coating, the coagulant is selected from aluminum sulfate, calcium carbonate or sodium silicate, and the retarder is selected from sodium citrate or sodium gluconate.

[0009] Preferably, the superhydrophobic coating material includes fluorinated silane, fluorinated polymer or silica-fluorinated silane composite material.

[0010] A method for manufacturing a novel lightweight heat-insulating building material, comprising the following steps: S1. Preparation of the precursor: Disperse nano-silica and graphene oxide in a solvent and perform ultrasonic treatment for 20 - 40 min; S2. Matrix mixing: Mix the cement-based material with the nano-dispersion obtained in step S1, stir for 30 min, and let stand for 12 - 24 h; S3. Foaming control: Add a foaming agent and uniformly mix at a stirring rate of 800 - 1500 rpm; S4. Curing treatment: After standing for 24 - 48 h, perform a stepwise temperature increase treatment at 50 - 80 °C for 2 - 4 h; S5. Sintering optimization: Sinter at a temperature of 650 - 850 °C for 1 - 3 h. Among them, when applied to a low-temperature environment, a low-temperature curing scheme of 250 - 450 °C can be adopted; S6. Surface modification: Deposit a superhydrophobic coating by chemical vapor deposition, and the coating is selected from fluorinated silane, fluorinated polymer or silica-fluorinated silane composite material.

[0011] Preferably, the solvent of the nano-dispersion is selected from deionized water, ethanol or a mixed solution thereof.

[0012] Preferably, before adding the foaming agent, uniformly disperse it by magnetic stirring for 30 min.

[0013] Preferably, the curing treatment adopts a two-step temperature increase method and gradually heats to the target temperature at a rate of 50 °C / h.

[0014] Preferably, the deposition temperature range of the superhydrophobic coating is 200 - 400 °C.

[0015] The present invention provides a novel lightweight heat-insulating building material and a manufacturing method thereof. It has the following beneficial effects: 1. The present invention adopts a combined regulation technology of multiple nanoparticles and foaming agents, achieving the effects of significantly reducing the material density and enhancing the heat insulation performance. Compared with the existing single cement system, this solution effectively overcomes the deficiencies of traditional materials being heavy and having fast heat conduction.

[0016] 2. The present invention adopts a dual protection technology of fiber reinforcement and superhydrophobic coating, achieving the effects of improving crack resistance and moisture resistance. Compared with the existing materials that only rely on traditional reinforcement methods, this solution solves the problems of easy cracking and moisture-induced aging in harsh environments.

[0017] 3. The present invention adopts a low-temperature sintering and stepwise temperature rise control technology, achieving the effects of reducing energy consumption and maintaining the integrity of the material structure. Compared with the existing high-temperature treatment technology, this solution alleviates the deficiencies of high process energy consumption and high risk of thermal damage.

[0018] 4. The present invention adopts an accurate raw material ratio and auxiliary component optimization technology, achieving the effects of improving the stability of the product and the process reproducibility. Compared with the existing single formulation design, this solution solves the defects of unstable ratio and poor repeatability during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart of the method steps of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] Please refer to the attached Figure 1 , the embodiments of the present invention provide a new type of lightweight heat-insulating building material and its manufacturing method. This material combines multiple nanotechnologies, adopts a specific raw material combination, and is prepared by a unique manufacturing method. It has excellent lightweight heat-insulating characteristics and can be widely used in the construction field, especially suitable for energy-saving buildings and environmental protection projects.

[0022] Raw Material Composition The raw materials of the new type of lightweight heat-insulating building material include, by mass: cement-based materials, foaming agents, nano-silica (SiO 2 ), graphene oxide (GO), carbon nanotubes (CNTs), silane coupling agents, fiber reinforcement materials, superhydrophobic coating materials, and other auxiliary components. According to actual needs, the proportions of each component can also be adjusted to adapt to different construction requirements and usage scenarios.

[0023] Cement-based Materials Cement-based materials are mainly used to provide the necessary strength and stability for the building materials. Common cement-based materials include Portland cement and alumina cement, and the latter can maintain better performance in high-temperature environments. According to specific needs, different cement-based materials can be selected and mixed to form a suitable matrix.

[0024] Foaming agent The foaming agent is used to generate foam, thereby increasing the porosity of the material and achieving a lightweight effect. Commonly used foaming agents include hydrogen peroxide (H 2 O 2 ), aluminum powder or silicon carbide micropowder (SiC), which can effectively release gas under specific conditions to form a stable foam structure.

[0025] Nano-silica (SiO 2 ) Nano-silica is an important reinforcing material that can improve the mechanical properties, thermal stability and heat insulation effect of composite materials. Through nano-sized SiO 2 particles, the density, strength and thermal conductivity of the material can be significantly improved, and the heat insulation effect can be enhanced.

[0026] Graphene oxide (GO) Graphene oxide plays an important role in enhancing the strength and thermal conductivity of materials. Its surface contains abundant functional groups, which can form good combinations with other components, improve the thermal conductivity of materials, and at the same time enhance their high-temperature resistance and corrosion resistance.

[0027] Carbon nanotubes (CNTs) Carbon nanotubes have extremely high thermal conductivity and mechanical strength, and can effectively improve the overall strength of materials. CNTs can also improve the electrical conductivity, thermal conductivity and crack resistance of materials, making them more stable and durable during use.

[0028] Silane coupling agent The silane coupling agent mainly plays a role in enhancing the interfacial bonding, improving the adhesion between cement-based materials and other components, and enhancing the comprehensive performance of materials.

[0029] Fiber-reinforced materials Fiber-reinforced materials such as polyvinyl alcohol (PVA) fibers and basalt fibers can enhance the toughness and crack resistance of materials. They effectively improve the bearing capacity and durability of materials under external forces and reduce the generation of cracks.

[0030] Superhydrophobic coating materials Superhydrophobic coating materials have excellent waterproof performance, can effectively prevent water penetration, and enhance the durability of materials. Commonly used coating materials include fluorosilane and nano-silica (SiO 2), which can significantly improve the waterproof performance of the material and avoid damage caused by water intrusion.

[0031] Other auxiliary components Other auxiliary components include dispersants, coagulants, retarders, bond enhancers, defoamers, pH regulators, surfactants, moisture-proof agents, etc. They can further optimize the formulation of the material and enhance its stability and workability. In particular, the dispersant helps the uniform distribution of nanoparticles in the matrix, prevents agglomeration, and ensures the uniformity and performance of the material.

[0032] Manufacturing method The process of manufacturing the new lightweight heat-insulating building material includes multiple steps. Each step needs to be strictly controlled to ensure the quality of the final product.

[0033] 1. Preparation of precursor Disperse nano-silica (SiO 2 ) and graphene oxide (GO) separately in a solvent, and use ultrasonic treatment technology. The ultrasonic treatment time is usually 20 - 40 minutes. Through this process, the nanoparticles can be uniformly dispersed, avoiding aggregation and enhancing the overall performance of the material.

[0034] 2. Matrix mixing Mix the nano-dispersion obtained in step 1 with the cement-based material, stir for 30 minutes, and then let it stand for 12 to 24 hours. This process helps the good combination of nanoparticles and the cement-based material, ensuring that the nanoparticles in the dispersion are uniformly combined with the cement-based material to form a composite structure.

[0035] 3. Foaming control After adding the foaming agent, mix uniformly at a stirring rate of 800 - 1500 rpm. The foaming agent reacts with other raw materials to release gas and form tiny bubbles. The control of the foaming process directly determines the lightweight characteristics of the material, so the stirring speed and the addition amount of the foaming agent need to be precisely controlled.

[0036] 4. Curing treatment The mixed material needs to stand for 24 - 48 hours to ensure the stability of the foam. Then carry out a stepwise temperature increase treatment at 50 - 80 °C for 2 - 4 hours. During the temperature increase process, the moisture gradually evaporates, and the foam gradually cures to form a solid foam structure.

[0037] 5. Sintering optimization Sinter the cured material at a high temperature of 650 - 850 °C for 1 - 3 hours to ensure the stability and strength of the material. If it is used in a low-temperature construction environment, a low-temperature curing scheme of 250 - 450 °C can be selected to meet the needs of different construction environments.

[0038] 6. Surface modification Finally, a superhydrophobic coating is deposited by chemical vapor deposition (CVD). The choice of the coating can be adjusted according to different usage environments and performance requirements. Commonly used coating materials include fluorosilanes, fluoropolymers, or silica-fluorosilane composites, which can provide excellent waterproof effects for the materials.

[0039] By adopting the above manufacturing method and raw material formula, the novel lightweight thermal insulation building material of the present invention has remarkable lightweight characteristics and excellent thermal insulation effects. It has a wide range of applications and is suitable for building materials that require high strength, low weight, and good thermal insulation performance.

[0040] Example 1 Steps and process parameters S1. Preparation of precursor: Disperse 3 parts of nano-silica (SiO 2 ) and 1.5 parts of graphene oxide (GO) in deionized water and perform ultrasonic treatment for 30 minutes to ensure uniform dispersion of the nanoparticles.

[0041] S2. Matrix mixing: Mix the dispersion obtained in step 1 with 55 parts of portland cement, stir for 20 minutes, and let it stand for 12 hours to allow the cement matrix to fully combine with the nanoparticles.

[0042] S3. Foaming control: Add 3.5 parts of hydrogen peroxide (H 2 O 2 ) as a foaming agent and uniformly mix it at a stirring rate of 1200 rpm to form a delicate and uniform foam structure.

[0043] S4. Curing treatment: After letting the mixture stand for 48 hours, perform a stepwise heating treatment at 60 °C for 3 hours to ensure foam stability.

[0044] S5. Sintering optimization: Put the cured material into a sintering furnace and perform sintering at 800 °C for 2 hours to ensure material strength and thermal stability.

[0045] S6. Surface modification: Deposit a superhydrophobic coating by chemical vapor deposition (CVD). The coating material is fluorosilane, the deposition temperature is 300 °C, and the treatment time is 30 minutes.

[0046] Component ratios Cement-based material: 55 parts Foaming agent: 3.5 parts Nano-silica (SiO 2 ): 3 parts Graphene oxide (GO): 1.5 parts Water: 20 parts Other auxiliary components (such as dispersants): 2 parts Superhydrophobic coating: 2 parts By combining foaming and nano-enhancement, the material density was successfully reduced, achieving the effect of being lightweight and having excellent heat insulation performance. At the same time, through the application of the superhydrophobic coating, the waterproof and crack resistance of the material were improved.

[0047] Example 2 Steps and process parameters S1. Preparation of precursor: Disperse 2 parts of nano-silica (SiO 2 ) and 1.5 parts of graphene oxide (GO) in ethanol, and perform ultrasonic treatment for 25 minutes to ensure uniform dispersion of nano-particles.

[0048] S2. Matrix mixing: Mix the dispersion in step 1 with 58 parts of alumina cement, stir for 25 minutes, and let it stand for 16 hours to uniformly combine the material components.

[0049] S3. Foaming control: Add 4 parts of aluminum powder as a foaming agent, mix evenly at a stirring speed of 1000 rpm, and the foam structure is uniform and delicate.

[0050] S4. Curing treatment: After the mixture stands for 36 hours, perform a stepwise temperature increase treatment at 70°C for 3 hours to ensure the improvement of material strength.

[0051] S5. Sintering optimization: In the low-temperature curing scheme, sinter at a temperature of 350°C for 2 hours to maintain the shape and thermal stability of the material.

[0052] S6. Surface modification: Coat a fluorinated polymer coating on the material surface by CVD method, the coating deposition temperature is 280°C, and treat for 40 minutes to significantly improve the waterproof and moisture-proof properties.

[0053] Component ratio Cement-based material: 58 parts Foaming agent: 4 parts Nano-silica (SiO 2 ) : 2 parts Graphene oxide (GO): 1.5 parts Water: 17 parts Other auxiliary components: 3 parts Superhydrophobic coating: 2 parts The application of the low-temperature sintering scheme significantly reduces energy consumption and enhances the thermal stability of the material. The superhydrophobic coating enhances the waterproof property, and the durability of the material in a humid environment is improved.

[0054] Example 3 Steps and process parameters S1. Preparation of precursor: Disperse 4 parts of nano-silica (SiO 2)(It is) ultrasonically dispersed with 2 parts of graphene oxide (GO) in ethanol for 35 minutes to ensure that the nanoparticles do not aggregate.

[0055] S2, Matrix mixing: Mix the dispersion obtained in step 1 with 53 parts of Portland cement, stir for 40 minutes, and let it stand for 24 hours to ensure uniform mixing and balanced material properties.

[0056] S3, Foaming control: Add 2.5 parts of silicon carbide micropowder (SiC) as a foaming agent, and the stirring rate is 1100 rpm to ensure a fine foam structure and uniform foaming.

[0057] S4, Curing treatment: After standing for 36 hours, carry out stepwise heating at a temperature of 70 °C for 3 hours to ensure the foam stability and remove excess moisture.

[0058] S5, Sintering optimization: Carry out sintering treatment at 750 °C for 2 hours to improve the material strength and heat resistance.

[0059] S6, Surface modification: Use the chemical vapor deposition (CVD) method to deposit a silica-silane fluoride composite coating on the material surface at a deposition temperature of 350 °C for 30 minutes.

[0060] Component ratio Cement-based material: 53 parts Foaming agent: 2.5 parts Nano-silica (SiO 2 ) : 4 parts Graphene oxide (GO): 2 parts Water: 22 parts Other auxiliary components: 3 parts Superhydrophobic coating: 2.5 parts The combination of the foaming agent and the nanoparticles effectively improves the lightness and heat insulation effect of the material. Low-temperature sintering optimizes the energy consumption, and the superhydrophobic coating improves the waterproof ability of the material, making its performance more stable in a humid environment.

[0061] Example 4 Steps and process parameters S1, Precursor preparation: Disperse 2.5 parts of nano-silica (SiO 2 ) and 2 parts of graphene oxide (GO) in deionized water, and carry out ultrasonic treatment for 30 minutes to ensure uniform particle dispersion.

[0062] S2, Matrix mixing: Mix the dispersion obtained in step 1 with 60 parts of Portland cement, stir for 20 minutes, and let it stand for 18 hours to ensure uniform matrix mixing.

[0063] S3, Foaming control: Add 5 parts of hydrogen peroxide (H2 O 2 ), as a foaming agent, is mixed under stirring at 1200 rpm to form fine and uniform foam.

[0064] S4. Curing treatment: After the mixture is left standing for 24 hours, it is subjected to a staged heating treatment at 65 °C for 2 hours to ensure the stability of the foam structure.

[0065] S5. Sintering optimization: Using a sintering temperature of 750 °C for 2 hours to ensure the stability of the material structure and improve the mechanical properties.

[0066] S6. Surface modification: A silicon fluoride alkane coating is coated by the CVD method, with a deposition temperature of 300 °C and a treatment time of 35 minutes to ensure excellent waterproof performance.

[0067] Component ratio Cement-based material: 60 parts Foaming agent: 5 parts Nano-silica (SiO 2 ) : 2.5 parts Graphene oxide (GO): 2 parts Water: 19 parts Other auxiliary components: 3 parts Superhydrophobic coating: 3 parts This example realizes low density and high heat insulation while saving energy consumption by adopting a low-temperature sintering process, and at the same time enhances the waterproof function. The coating enables the material to have better moisture resistance and meets the usage requirements in different climate environments.

[0068] Comparative example 1 (Traditional process comparison scheme based on Example 1) Raw material ratio Cement-based material: 60% Foaming agent: 3.5% Ordinary silicon powder (replacing nano-silica and graphene oxide): 4% Water: 25% Other auxiliary components: 2% Conventional waterproof agent (replacing superhydrophobic coating): 5% Specific steps S1. Mixing preparation: Mix 60% of cement with 25% of water and stir for 15 minutes.

[0069] S2. Filler addition: Add 4% of ordinary silicon powder and 2% of auxiliary components and continue to stir for 10 minutes.

[0070] S3. Foaming treatment: Add 3.5% of foaming agent and stir at 1100 rpm for 4 minutes to uniformly generate foam.

[0071] S4, Curing treatment: Naturally cure for 36 hours without temperature-controlled heating-up.

[0072] S5, Sintering treatment: Sinter at 750 °C for 1.5 hours.

[0073] S6, Surface treatment: Coating with a conventional waterproof agent, using the spraying method, and treating at room temperature for 20 minutes.

[0074] Compared with Example 1, the comparative example solution does not introduce nanomaterials and the superhydrophobic CVD process, but uses traditional silicon powder filling and waterproof spraying, which easily leads to insufficient heat insulation and crack resistance performance.

[0075] Comparative Example 2 (Low-temperature curing comparison solution based on Example 2) Raw material ratio Cement-based material: 60% Foaming agent: 4% Nano-silica (SiO 2 ) : 2% Graphene oxide (GO): 1% Water: 20% Other auxiliary components: 3% Without superhydrophobic coating Specific steps S1, Preparation of precursor: Disperse 2 parts of nano-silica and 1 part of graphene oxide in 20% water and ultrasonically treat for 20 minutes.

[0076] S2, Matrix mixing: Add 60% of alumina cement, stir for 20 minutes and then stand for 14 hours.

[0077] S3, Foaming control: Add 4% of aluminum powder and stir at 1000 rpm for 3 minutes.

[0078] S4, Curing treatment: Stand for 30 hours and naturally cure without stepwise heating-up.

[0079] S5, Sintering treatment: Sinter at 800 °C for 2 hours.

[0080] S6, Surface treatment: Use the traditional dipping method and treat at room temperature for 20 minutes without using the CVD process.

[0081] This solution simplifies the process in both the preparation of the precursor and the curing steps, does not use stepwise heating-up and the superhydrophobic coating, which easily reduces the moisture resistance and overall stability of the material.

[0082] Comparative Example 3 (High-temperature sintering comparison solution based on Example 3) Raw material ratio Cementitious material: 53% Foaming agent: 2.5% Nanosilica (SiO 2 ) : 3% Graphene oxide (GO): 1% Water: 25% Other auxiliary components: 3% Without superhydrophobic coating Specific steps S1. Preparation of precursor: Disperse 3 parts of nanosilica and 1 part of graphene oxide in 25% water and ultrasonically treat for 25 minutes.

[0083] S2. Matrix mixing: Mix with 53% portland cement, stir for 30 minutes, and let stand for 20 hours.

[0084] S3. Foaming treatment: Add 2.5% silicon carbide micropowder and stir at 1100 rpm for 4 minutes.

[0085] S4. Curing treatment: Shorten the curing time to 30 hours and treat at 70 °C for 2 hours.

[0086] S5. Sintering treatment: Raise the sintering temperature to 800 °C and control the time at 1.5 hours.

[0087] S6. Surface treatment: Coat the waterproof agent by traditional spraying method and treat at room temperature for 15 minutes.

[0088] Compared with Example 3, this comparative example scheme increases the sintering temperature, shortens the curing and surface treatment steps, and does not use CVD-deposited superhydrophobic coating, which may lead to poor thermal stability and moisture-proof performance.

[0089] Comparative Example 4 (Traditional surface treatment comparison scheme based on Example 4) Raw material ratio Cementitious material: 60% Foaming agent: 5% Nanosilica (SiO 2 ) : 2.5% Graphene oxide (GO): 2% Water: 19% Other auxiliary components: 3% Without superhydrophobic coating (replaced by dip coating process) Specific steps S1. Mixing and dispersion: Dissolve 2.5 parts of nanosilica and 2 parts of graphene oxide in 19% water and ultrasonically treat for 20 minutes.

[0090] S2. Substrate Preparation: Add 60% cement, stir for 15 minutes, and then let it stand for 18 hours.

[0091] S3. Foaming Treatment: Add 5% hydrogen peroxide and stir at 1200 rpm for 3 minutes.

[0092] S4. Curing Treatment: Let it stand for 24 hours for natural curing without temperature control steps.

[0093] S5. Sintering Treatment: Sinter at 750 °C for 1.5 hours.

[0094] S6. Surface Treatment: Coating with waterproof agent by traditional dip - coating process, dip - coat at room temperature for 25 minutes without CVD deposition.

[0095] Different from Example 4, this comparative - example solution abandons the CVD process and uses traditional dip - coating treatment, which is likely to result in inferior waterproof and moisture - proof properties compared to the super - hydrophobic coating solution of the present invention.

[0096] Experimental Example Experimental Purpose Verify the comprehensive performance of the novel lightweight thermal - insulating building material of the present invention, including lightness, heat insulation, waterproofness, and durability, and clarify the creative improvement of the present invention compared with traditional technologies by comparing with comparative - example embodiments.

[0097] Experimental Materials and Equipment Test Samples: Example Group: Building - material samples prepared in Examples 1 to 4.

[0098] Comparative - example Group: Building - material samples prepared in Comparative - example Embodiments 1 to 4.

[0099] Test Equipment: Thermal - conductivity measuring instrument (ISO8301 standard).

[0100] Electronic density meter (ASTMC642 standard).

[0101] Universal mechanical testing machine (ASTMC39 standard).

[0102] Thermostatic and humidistatic chamber (simulating humid and hot environment).

[0103] High - pressure spraying device (simulating heavy - rain scouring).

[0104] Micro - CT scanner (pore - structure analysis).

[0105] Experimental Methods and Procedures 1. Lightness Test Steps: Cut the sample into a standard block of 10 cm×10 cm×5 cm.

[0106] Measure the bulk density using an electronic densitometer and compare the examples with the control groups.

[0107] Data recording: Density values of each sample (kg / m³).

[0108] 2. Thermal insulation performance test Steps: Place the sample between the two heating plates of the thermal conductivity measuring instrument.

[0109] Keep the temperature difference ΔT = 25 °C constant and record the heat transfer rate.

[0110] Data recording: Thermal conductivity (W / m·K).

[0111] 3. Waterproof and durability test Steps: Thermostatic and humidistatic chamber: Temperature 40 °C, humidity 90%, for 30 days.

[0112] High-pressure spraying: Water pressure 0.3 MPa, continuous spraying for 2 hours.

[0113] Weigh the sample after spraying and calculate the water absorption rate (%).

[0114] Use micro-CT to scan the pore structure and observe the closed pore rate (%).

[0115] 4. Mechanical property test Steps: Conduct a compressive strength test using a universal mechanical testing machine.

[0116] Loading rate 1 mm / min, record the failure load (MPa).

[0117] Experimental data table: The introduction of nanoparticles significantly optimizes the internal structure of the material. The dispersion effect of silica and graphene oxide improves the closed pore rate, and the foam structure is more uniform and dense, thus reducing the thermal conductivity. In the traditional control group, ordinary silicon powder cannot form a stable nano-scale interface, the heat transfer path is shorter, and the thermal insulation performance is weak.

[0118] The CVD deposition process of the superhydrophobic coating is the key difference. The coating in the example is tightly bonded to the substrate, the water contact angle > 150°, effectively blocking water penetration. The spraying or dipping process in the control group cannot form a nano-scale hydrophobic layer, the water absorption rate is significantly higher, and it is prone to cracking in a humid and hot environment.

[0119] The low-temperature sintering combined with the stepwise heating curing strategy reduces the damage to nanostructures caused by high temperatures. The compressive strength of the materials in the examples is generally higher than that of the comparative examples, indicating that the process optimization enhances the toughness of the materials. The high-temperature sintering of the comparative examples results in pore collapse, a decrease in mechanical properties, and a reduction in the closed pore rate.

[0120] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new type of lightweight thermal insulation building material, characterized in that: include: 50-60 parts of cement-based materials; 1-5 parts of foaming agent; 3-8 parts of nano silicon dioxide; 0.5-3 parts of graphene oxide; 0.1-1 part of carbon nanotubes; Silane coupling agent 0.2-1 part; Fiber reinforcement material 0.5-3 parts; 0.2-1 part of super hydrophobic coating material; 3-7 parts of other auxiliary ingredients, wherein the auxiliary ingredients are selected from one or more of dispersants, accelerators, retarders, adhesion enhancers, defoamers, pH regulators, surfactants, and moisture-proofing agents; 15-30 parts of water.

2. The novel lightweight heat-insulating building material according to claim 1 is characterized in that: The cement-based material is silicate cement, alumina cement or a mixture thereof.

3. The novel lightweight heat-insulating building material according to claim 1 is characterized in that: The foaming agent is selected from hydrogen peroxide, aluminum powder or silicon carbide powder, and the dispersant is selected from polycarboxylic acid water reducer, polyvinyl alcohol or sodium lauryl sulfate.

4. The novel lightweight heat-insulating building material according to claim 1 is characterized in that: The fiber reinforcement material is selected from polyvinyl alcohol fiber, basalt fiber or a combination thereof, the moisture-proof agent is selected from silane, silicone emulsion or fluoride coating, the coagulant is selected from aluminum sulfate, calcium carbonate or sodium silicate, and the retarder is selected from sodium citrate or sodium gluconate.

5. The novel lightweight heat-insulating building material according to claim 1 is characterized in that: The super hydrophobic coating material includes fluorinated silane, fluorinated polymer or silicon dioxide-fluorinated silane composite material.

6. A method for manufacturing a novel lightweight heat-insulating building material, used for manufacturing the novel lightweight heat-insulating building material according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Precursor preparation: dispersing nano-silicon dioxide and graphene oxide in a solvent and ultrasonically treating for 20-40 min; S2, matrix mixing, mixing the cement-based material with the nano-dispersion obtained in step S1, stirring for 30 minutes, and standing for 12-24 hours; S3, foaming control, adding foaming agent, and mixing evenly at a stirring rate of 800-1500 rpm; S4, curing treatment, after standing for 24-48 hours, perform step-by-step heating treatment at 50-80°C for 2-4 hours; S5, sintering optimization, sintering at 650-850℃ for 1-3h. When applied in low temperature environment, a low temperature curing solution of 250-450℃ can be adopted; S6. Surface modification: depositing a super hydrophobic coating by chemical vapor deposition, wherein the coating is selected from fluorinated silane, fluorinated polymer or silicon dioxide-fluorinated silane composite material.

7. The method for manufacturing the novel lightweight heat-insulating building material according to claim 6, characterized in that: The solvent of the nano-dispersion liquid is selected from deionized water, ethanol or a mixed solution thereof.

8. The method for manufacturing the novel lightweight heat-insulating building material according to claim 6, characterized in that: Before adding the foaming agent, it is evenly dispersed by magnetic stirring for 30 minutes.

9. The method for manufacturing the novel lightweight heat-insulating building material according to claim 6, characterized in that: The curing process adopts a two-step heating method, gradually heating to the target temperature at a rate of 50° C. / h.

10. The method for manufacturing the novel lightweight heat-insulating building material according to claim 6, characterized in that: The deposition temperature of the super hydrophobic coating is in the range of 200-400°C.

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