Composite heat preservation and sound insulation building block

Abstract

Belonging to the technical field of building materials, the invention provides a composite thermal insulation and sound insulation building block, which is prepared by mixing the following raw materials by mass: 660-720 parts of cement, 210-240 parts of fly ash, 40-60 parts of fiber / modified silica aerogel, 300-350 parts of water, 4.5-10 parts of a water reducer, and 52-97 parts of prefabricated foam. Wherein the fiber / modified silicon dioxide aerogel is prepared by uniformly mixing tetraethyl orthosilicate, ethanol and water, adding a gamma-aminoethyl aminopropyl trimethoxy silane ethanol water solution, mixing and stirring, adjusting the pH value to be acidic, performing ultrasonic treatment, adjusting the pH value to be alkaline, adding a fiber suspension, performing ultrasonic treatment, aging and performing freeze-drying treatment; the prefabricated foam is prepared by mixing nano aluminum oxide, nano silicon dioxide and water, performing ultrasonic treatment, adding a surfactant, performing magnetic stirring to obtain foaming liquid and finally using an air compressor. The sound-insulation and heat-preservation building material has a certain sound-insulation effect while achieving good heat-preservation performance.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, in particular to a composite thermal insulation and sound insulation building block. Background Art

[0002] In traditional architecture, commonly used wall materials such as bricks and concrete were once the primary choice due to their high strength and durability. However, despite their excellent mechanical properties, these materials suffer from heat transfer through exterior walls, leading to internal temperature fluctuations and increased energy consumption for air conditioning, heating, and other equipment. This heat loss not only increases the building's energy burden but also places significant strain on the environment.

[0003] Furthermore, with the acceleration of urbanization and the development of the construction industry, the requirements for energy conservation, environmental protection, and comfort in buildings are becoming increasingly higher. In modern building design, heat and noise are two common problems that continue to threaten the rental comfort and living experience of modern buildings. At present, in order to achieve sound insulation and thermal insulation performance and meet energy-saving and environmental protection requirements, new materials such as foam concrete and lightweight blocks are gradually entering the construction field. These materials are not only lightweight and easy to construct, but also have good thermal insulation and sound insulation performance. However, traditional foam concrete and lightweight blocks have poor stability, are prone to dust generation, have poor waterproof performance, high water absorption, and have the microstructure characteristics of interconnected pores, resulting in less than ideal thermal insulation performance.

[0004] To address these issues, silica aerogel is gaining increasing attention as a new filler for thermal insulation and sound insulation. Silica aerogel's unique nano-network structure and high porosity give it low thermal conductivity. Its high surface area and complex pore structure aid in the scattering and dissipation of sound waves, imparting acoustic delay properties that have led to its application as a filler for thermal insulation and sound insulation. However, due to its brittleness and structural collapse, silica aerogel can easily lead to irreversible structural collapse when added to composite materials, resulting in a loss of thermal and sound insulation performance in practical applications.

[0005] Therefore, it is necessary to provide a composite thermal insulation and sound insulation building block to solve the problems existing in the above-mentioned prior art. Summary of the Invention

[0006] In view of this, the present invention provides a composite thermal insulation and sound insulation building block, which can achieve good thermal insulation performance and a certain sound insulation effect.

[0007] To achieve the above object, the present invention provides a composite thermal insulation and sound insulation building block, which is prepared by mixing the following raw materials in parts by weight: 660-720 parts of cement, 210-240 parts of fly ash, 40-60 parts of fiber / modified silica aerogel, 300-350 parts of water, 4.5-10 parts of water reducer, 52-97 parts of prefabricated foam, and 40-60 parts of hydrophobic mixture; The fiber / modified silica aerogel is prepared by mixing tetraethyl orthosilicate, ethanol and deionized water, adding γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution and stirring, adjusting the pH value to acidic, ultrasonically treating, adjusting the pH value to alkaline, adding a fiber suspension, ultrasonically treating, aging, impregnating with a n-hexane / ethanol mixed solution, and freeze-drying. The fiber suspension is a plant fiber suspension, which is prepared by adding plant fibers to an ethanol solution, soaking them, and ultrasonically treating them. The prefabricated foam is prepared by mixing nano-alumina, nano-silicon dioxide and water, ultrasonically treating, adding a surfactant, and magnetically stirring to prepare a foaming liquid, and finally using an air compressor; The hydrophobic mixture is made of polydimethylsiloxane, tetraethyl orthosilicate, and dibutyltin dilaurate; The composite thermal insulation and sound insulation building block is prepared by the following preparation method: The cement, fly ash, and fiber / modified silica aerogel are mixed and stirred, and then water and polycarboxylate water reducer are added and continued to be stirred. Then, the hydrophobic mixture is added and stirred alternately at slow and fast speeds. The prefabricated foam is added and slowly stirred until completely dispersed. Then, the mixture is poured into a mold, covered with plastic wrap, allowed to stand, and demolded to obtain a composite thermal insulation and sound insulation block.

[0008] The present invention prepares fiber / modified silica aerogel as a filler to improve the thermal insulation performance of composite thermal insulation and sound insulation blocks. Silica aerogel has low density and ultra-low thermal conductivity, and its highly open pore structure slows heat transfer. This enables it to provide excellent thermal insulation performance, thereby imparting a certain degree of thermal insulation to the overall composite block. However, using silica aerogel alone as a filler significantly reduces the mechanical properties of the composite block, causing the overall structure to collapse. The present invention uses tetraethyl orthosilicate as a silica precursor and γ-aminoethylaminopropyltrimethoxysilane as a modifier. In an alkaline environment, tetraethyl orthosilicate and γ-aminoethylaminopropyltrimethoxysilane are dehydrated and condensed to form a network backbone structure of silica gel, while forming a dense cross-linked network with the fiber. The hydroxyl groups on the surface of the fiber form hydrogen bonds or covalent bonds with the amino groups of γ-aminoethylaminopropyltrimethoxysilane, thereby improving the interfacial bonding ability between the fiber and the silica aerogel, thereby improving the interfacial bonding strength between the two, and improving the shortcomings of the silica aerogel alone, such as certain brittleness and easy structural collapse. In addition, the fiber itself can play a role in buffering stress when added to the matrix, and the tightly cross-linked structure formed by the two can also effectively prevent the generation and expansion of cracks; the modified silica aerogel also effectively isolates the thermal conductivity between the fibers, thereby reducing thermal bridges and heat transfer in the overall material, and ultimately improving its thermal insulation performance. The highly open pore structure of silica aerogel and the cross-linked network structure of fiber / modified silica aerogel greatly increase the porosity of the material. The complex pore structure helps to reflect and scatter low-frequency sound waves, thereby effectively disrupting their propagation path and further improving the overall sound insulation performance.

[0009] The present invention uses nanoparticles to stabilize foam, acting as stabilizers within the foam structure by enhancing interfacial strength and overall stability, allowing for the production of foam-based composite building blocks. The nanoparticles adsorb at the gas-liquid interface of the foam film, reducing the gas-liquid contact area and slowing the foam dissolution rate, thereby enhancing foam stability. Furthermore, the presence of the nanoparticles within the film reduces the foam's diffusion rate and hinders the flow of the foam liquid, helping to maintain a low surface tension within the film and thus improving foam stability. Furthermore, nanosilica reacts with Ca(OH)2 to promote cement hydration, while nanoalumina acts as a filler in cement-based composite materials, resulting in a denser microstructure. Therefore, the addition of nanosilica and nanoalumina to the foam simultaneously stabilizes the foam and promotes hydration. The resulting foam-based composite building block features uniformly distributed pores, effectively attenuating the propagation of sound waves and reducing their transmission efficiency, thereby achieving sound insulation. Furthermore, the presence of internal pores reduces heat conduction, further enhancing the overall thermal insulation effect.

[0010] A water-reducing agent is added to the components of the present invention to improve the fluidity of the slurry. The addition of the fiber / modified silica aerogel component not only has thermal insulation and sound insulation effects, but also has thickening and water retention properties. By adopting the above-mentioned mass proportion matching ratio, the prepared composite thermal insulation and sound insulation building block can achieve good thermal insulation performance and sound insulation effect, and can meet the overall mechanical strength requirements.

[0011] Optionally, the mass ratio of polydimethylsiloxane, tetraethyl orthosilicate and dibutyltin dilaurate in the hydrophobic mixture is 100:10:1.

[0012] The components of the present invention contain a hydrophobic mixture, wherein polydimethylsiloxane is used to perform super-hydrophobic modification on the base material, tetraethyl orthosilicate serves as a crosslinking agent for the polydimethylsiloxane, and dibutyltin dilaurate serves as a reaction catalyst. The hydrophobic modification can reduce the water absorption rate of the overall composite building block, further reducing heat dissipation to improve the thermal insulation effect.

[0013] Optionally, the plant fiber suspension is prepared by adding plant fibers to an ethanol solution with a volume concentration of 30%, soaking the solution for 40 minutes, and then ultrasonically treating the solution for 15 minutes.

[0014] Optionally, the fiber / modified silica aerogel is prepared by mixing tetraethyl orthosilicate, ethanol and deionized water and stirring for 15 to 20 minutes, adding γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution and stirring for 15 to 20 minutes, adding hydrochloric acid to adjust the pH value to 2 to 3, ultrasonically treating at 20 to 30°C for 10 to 30 minutes, adding ammonia water to adjust the pH value to 7.2 to 8, adding fiber suspension and ultrasonically treating at 50°C for 30 to 50 minutes, aging for 24 to 36 hours, adding n-hexane / ethanol mixed solution and immersing for 6 to 8 hours, and freeze-drying for 24 to 36 hours.

[0015] During the preparation process of the present invention, the aerogel is finally immersed in a mixed solution of n-hexane / ethanol to strengthen the main chain structure of the aerogel network and improve the overall strength.

[0016] Optionally, the mass concentration of the γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution is 30% to 50%.

[0017] Optionally, the prefabricated foam is prepared by mixing nano-alumina, nano-silicon dioxide and water, ultrasonically treating for 10 to 20 minutes, adding a surfactant, and magnetically stirring at 200 rpm at room temperature for 2 to 3 hours to prepare a foaming liquid, and finally using an air compressor.

[0018] Optionally, the surfactant is one of sodium dodecylbenzene sulfonate, sodium polyvinyl alcohol sulfonate, and sodium stearate.

[0019] Optionally, the composite thermal insulation and sound insulation building block is prepared by the following preparation method: Cement, fly ash, and fiber / modified silica aerogel were mixed and stirred for 2 to 5 minutes, and then water and polycarboxylate water reducer were added and stirred for 2 to 5 minutes. Then, the hydrophobic mixture was added and stirred alternately at slow and fast speeds for 2 to 5 minutes each. Prefabricated foam was added and stirred slowly until completely dispersed. Then, the mixture was poured into a mold, covered with plastic wrap, and allowed to stand at 20 to 30°C for 36 to 48 hours. The composite thermal insulation and sound insulation blocks were demoulded to obtain the composite thermal insulation and sound insulation blocks.

[0020] In the present invention, after the slurry is poured into the mold, the mold is covered with a preservative film to prevent water evaporation.

[0021] Optionally, the plant fiber is obtained by scraping off the outer layer of pineapple leaves with a manual spatula, extracting the inner fibers by combing and manual methods, rinsing with water, drying at room temperature for 36 to 48 hours, and then cutting.

[0022] The present invention extracts the fibers inside the pineapple leaves and then rinses them with water to remove impurities. When the plant leaves are reused as plant fibers as fillers, the total discard of potentially useful materials can be minimized, thereby ensuring good environmental sustainability.

[0023] The above technical solution of the present invention includes at least the following beneficial effects: 1. This invention effectively improves thermal and sound insulation performance by grafting modified silica aerogel onto fibers as a filler in composite thermal insulation and sound insulation blocks. While silica aerogel provides excellent thermal insulation, its use alone can reduce overall mechanical properties. The interface between the modified aerogel and the fibers enhances structural strength, preventing cracks. Furthermore, by isolating the thermal conductivity between the fibers, thermal bridges are reduced, improving insulation effectiveness.

[0024] 2. This invention stabilizes the foam structure and promotes cement hydration by adding nano-silica and nano-alumina to the foam. The nanoparticles adsorb within the foam liquid film, enhancing foam stability, reducing the contact area at the gas-liquid interface, and slowing the foam dissolution rate. Nano-silica promotes cement hydration, while the filling action of nano-alumina creates a dense microstructure, enhancing the mechanical strength of the foam. The uniform distribution of pores within the foam composite building block effectively attenuates sound wave transmission, improving sound insulation, while also reducing heat conduction and enhancing thermal insulation. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0026] Preparation: 60 parts of polydimethylsiloxane, 6 parts of tetraethyl orthosilicate, and 0.6 parts of dibutyltin dilaurate were mixed to obtain a hydrophobic mixture.

[0027] Example 1 700 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods. The leaves were rinsed with water, dried at room temperature for 48 hours, and then cut. After cutting, the leaves were added to 1000 parts of 30% ethanol solution, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, i.e., fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 20 minutes, 400 parts of 40% γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution were added and stirred for 40 minutes, hydrochloric acid was added to adjust the pH value to 2, ultrasonically treated at 30°C for 40 minutes, ammonia water was added to adjust the pH value to 7.6, 150 parts of fiber suspension were added, ultrasonically treated at 50°C for 50 minutes, aged for 36 hours, added to 100 parts of n-hexane / ethanol mixed solution, immersed for 8 hours, and finally freeze-dried for 36 hours to prepare fiber / modified silica aerogel.

[0028] 2 parts of nano-alumina, 1 part of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 20 minutes, 4 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 3 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0029] 700 parts of cement, 220 parts of fly ash, and 60 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes. Then, 350 parts of water and 8 parts of polycarboxylate superplasticizer were added and stirred for another 2 minutes. Next, 60 parts of the hydrophobic mixture were added, stirring alternately at a slow and fast speed for 5 minutes each. Finally, 85 parts of prefabricated foam were added to the slurry and stirred slowly until completely dispersed. The mixture was then poured into a mold with a metal mesh bottom, covered with plastic wrap, and allowed to stand at 30°C for 48 hours before demolding to produce the composite thermal insulation and sound insulation blocks.

[0030] Example 2 500 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods. The leaves were rinsed with water, dried at room temperature for 36 hours, and then cut. After cutting, the leaves were added to 1000 parts of 30% ethanol solution by volume, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, i.e., fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 15 minutes, 200 parts of 30% γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution were added and stirred for 20 minutes, hydrochloric acid was added to adjust the pH value to 3, ultrasonically treated at 20°C for 20 minutes, ammonia was added to adjust the pH value to 7.2, 120 parts of fiber suspension were added, ultrasonically treated at 50°C for 40 minutes, aged for 24 hours, added to 100 parts of n-hexane / ethanol mixed solution and immersed for 6 hours, and finally freeze-dried for 24 hours to prepare fiber / modified silica aerogel.

[0031] 1.5 parts of nano-alumina, 1.5 parts of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 10 minutes, 2.5 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 2 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0032] 660 parts of cement, 210 parts of fly ash, and 40 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes. Then, 300 parts of water and 4.5 parts of polycarboxylate superplasticizer were added and stirred for another 2 minutes. Next, 40 parts of the hydrophobic mixture were added, stirring alternately at a slow and fast speed for 2 minutes each. Finally, 72 parts of prefabricated foam were added to the slurry and stirred slowly until completely dispersed. The mixture was then poured into a mold with a metal mesh bottom, covered with plastic wrap, and allowed to stand at 20°C for 36 hours before demolding to produce the composite thermal insulation and sound insulation blocks.

[0033] Example 3 800 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods. The leaves were rinsed with water, dried at room temperature for 40 hours, and then cut. After cutting, the leaves were added to 1000 parts of 30% ethanol solution by volume, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, namely: fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 18 minutes, 300 parts of 40% γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution were added and stirred for 30 minutes, hydrochloric acid was added to adjust the pH value to 2.4, ultrasonically treated at 25°C for 40 minutes, ammonia was added to adjust the pH value to 8, 145 parts of the fiber suspension were added, ultrasonically treated at 50°C for 50 minutes, aged for 30 hours, added to 100 parts of n-hexane / ethanol mixed solution and immersed for 7 hours, and finally freeze-dried for 28 hours to prepare fiber / modified silica aerogel.

[0034] 1.7 parts of nano-alumina, 1.2 parts of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 15 minutes, 4 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 2.5 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0035] 680 parts of cement, 220 parts of fly ash, and 50 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes. Then, 310 parts of water and 10 parts of polycarboxylate superplasticizer were added and stirred for another 2 minutes. Next, 50 parts of the hydrophobic mixture were added, stirring alternately at a slow and fast speed for 4 minutes each. Finally, 97 parts of prefabricated foam were added to the slurry and stirred slowly until completely dispersed. The mixture was then poured into a mold with a metal mesh bottom, covered with plastic wrap, and allowed to stand at 25°C for 42 hours before demolding to produce the composite thermal insulation and sound insulation blocks.

[0036] Example 4 600 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods, rinsed with water, dried at room temperature for 40 hours, and cut. After cutting, the leaves were added to 1000 parts of 30% ethanol solution by volume, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, namely: fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 18 minutes, and 350 The fiber / modified silica aerogel was prepared by mixing 130 parts of γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution with a mass concentration of 35% and stirring for 25 minutes, adding hydrochloric acid to adjust the pH value to 2.2, ultrasonically treating at 30°C for 45 minutes, adding ammonia water to adjust the pH value to 7.8, adding 130 parts of fiber suspension and ultrasonically treating at 50°C for 45 minutes, aging for 28 hours, adding 100 parts of n-hexane / ethanol mixed solution and immersing for 6.5 hours, and finally freeze-drying for 32 hours to obtain the fiber / modified silica aerogel.

[0037] 1.6 parts of nano-alumina, 1 part of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 12 minutes, 3 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 2.5 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0038] 720 parts of cement, 230 parts of fly ash, and 50 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes. Then, 330 parts of water and 7.5 parts of polycarboxylate superplasticizer were added and stirred for another 2 minutes. Next, 45 parts of the hydrophobic mixture were added and stirred alternately at a slow and fast speed for 4 minutes each. Finally, 74 parts of prefabricated foam were added to the slurry and stirred slowly until completely dispersed. The mixture was then poured into a mold with a metal mesh bottom, covered with plastic wrap, and allowed to stand at 20°C for 48 hours before demolding to obtain the composite thermal insulation and sound insulation blocks.

[0039] Example 5 800 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods, rinsed with water, dried at room temperature for 45 hours, and cut. After cutting, the leaves were added to 1000 parts of ethanol solution with a volume concentration of 30%, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, namely: fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 20 minutes, and 400 parts of Parts of γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution with a mass concentration of 30% were mixed and stirred for 40 minutes, hydrochloric acid was added to adjust the pH value to 2.5, and ultrasonic treatment was performed at 20°C for 50 minutes. Ammonia water was added to adjust the pH value to 7.7, 100 parts of fiber suspension was added and ultrasonic treatment was performed at 50°C for 30 minutes, and then aged for 28 hours. 100 parts of n-hexane / ethanol mixed solution was added and immersed for 6.5 hours, and finally freeze-dried for 30 hours to obtain fiber / modified silica aerogel.

[0040] 2 parts of nano-alumina, 1.1 parts of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 20 minutes, 4 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 3 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0041] 660 parts of cement, 240 parts of fly ash, and 40 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes, followed by the addition of 350 parts of water and 10 parts of polycarboxylate superplasticizer and continued stirring for 2 minutes. Finally, 52 parts of prefabricated foam were added to the slurry and slowly stirred until completely dispersed. The mixture was then poured into a mold with a metal mesh at the bottom, covered with plastic wrap, and allowed to stand at 30°C for 40 hours before demolding to obtain a composite thermal insulation and sound insulation block.

[0042] Example 6 800 parts of pineapple leaves were scraped off the outer layer with a manual spatula, and the internal fibers were extracted by combing and manual methods. The leaves were rinsed with water, dried at room temperature for 48 hours, and then cut. After cutting, the leaves were added to 1000 parts of 30% ethanol solution by volume, soaked for 40 minutes, and ultrasonically treated for 15 minutes to prepare a plant fiber suspension, namely: fiber suspension; 200 parts of tetraethyl orthosilicate, 2000 parts of ethanol and 1000 parts of deionized water were mixed and stirred for 16 minutes, 350 parts of 30% γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution were added and stirred for 30 minutes, hydrochloric acid was added to adjust the pH value to 2.6, ultrasonically treated at 25°C for 40 minutes, ammonia was added to adjust the pH value to 8, 110 parts of the fiber suspension were added and ultrasonically treated at 50°C for 35 minutes, aged for 36 hours, added to 100 parts of n-hexane / ethanol mixed solution and immersed for 6 hours, and finally freeze-dried for 36 hours to prepare fiber / modified silica aerogel.

[0043] 2 parts of nano-alumina, 1 part of nano-silica and 100 parts of water were mixed and stirred, ultrasonically treated for 15 minutes, 3 parts of surfactant were added, and magnetic stirring was carried out at a speed of 200 rpm at room temperature for 2.5 hours to prepare a foaming liquid, and finally an air compressor was used to prepare prefabricated foam.

[0044] 700 parts of cement, 220 parts of fly ash, and 45 parts of fiber / modified silica aerogel were mixed and stirred for 2 minutes. Then, 310 parts of water and 6 parts of polycarboxylate superplasticizer were added and stirred for another 2 minutes. Next, 45 parts of the hydrophobic mixture were added, stirring alternately at a slow and fast speed for 4 minutes each. Finally, 77 parts of prefabricated foam were added to the slurry and stirred slowly until completely dispersed. The mixture was then poured into a mold with a metal mesh bottom, covered with plastic wrap, and allowed to stand at 25°C for 48 hours before demolding to produce the composite thermal insulation and sound insulation blocks.

[0045] The present invention also carried out comparative examples and related tests.

[0046] Comparative Example 1 Compared with Example 1, the only difference is that no fiber suspension is added, and the other preparation methods and components are completely the same, and finally a composite thermal insulation and sound insulation block is obtained.

[0047] Comparative Example 2 Compared with Example 1, the only difference is that nano-alumina and nano-silicon dioxide are not added to the prefabricated foam. Other preparation methods and components are exactly the same, and finally a composite thermal insulation and sound insulation building block is obtained.

[0048] Comparative Example 3 Compared with Example 1, the only difference is that the fiber / modified silica aerogel component is not prepared, and the silica aerogel and fiber are directly added. The other preparation methods and components are exactly the same, and finally a composite thermal insulation and sound insulation block is obtained.

[0049] Performance testing The compressive strength and flexural strength tests of the samples prepared in Examples 1 to 6 and Comparative Examples 1 to 3 were performed in accordance with the national standard GB / T4111-2013 Test Methods for Concrete Blocks and Bricks to evaluate their mechanical properties. The samples prepared in Examples 1 to 6 and Comparative Examples 1 to 3 were tested for thermal conductivity using the guarded hot plate method according to the national standard GB / T10294-2008 for determination of steady-state thermal resistance and related properties of thermal insulation materials, and for density using the national standard GB / T29060-2012 for composite insulating bricks and composite insulating blocks to evaluate their thermal insulation performance. The water resistance test of the samples prepared in Examples 1 to 6 and Comparative Examples 1 to 3 was carried out with reference to the JGJ / T12-2019 lightweight aggregate concrete application technical standard. The test was as follows: after the samples were cured for 28 days, they were dried in an oven at 105±5°C until the mass was constant. After the samples were immersed in water for 48 hours, the mass of the specimens was tested, and the water absorption rate was calculated according to formula (I); (I) Where w is the saturated water absorption rate, m1 is the mass of the dry sample; m0 is the mass of the saturated sample; The samples prepared in Examples 1 to 6 and Comparative Examples 1 to 3 were tested for sound absorption coefficient in the frequency range of 50 Hz to 1700 Hz in accordance with ISO 10534-2:1998, Measurement of sound absorption coefficient and acoustic impedance in acoustic impedance tubes - Part 2: Transfer function method, to evaluate the sound insulation performance of the samples. The test results of the compressive strength, flexural strength, thermal conductivity, density, water absorption and sound absorption coefficient of the samples prepared in Examples 1 to 6 and Comparative Examples 1 to 3 are shown in Table 1.

[0050] Table 1

[0051] As shown in Table 1, the mechanical strength of Examples 1 to 6 is significantly higher than that of Comparative Examples 1 to 3, and the thermal insulation and sound insulation properties are also good.

[0052] Analysis of the experimental data in Table 1 shows that, compared to Comparative Examples 1 and 3, the addition of fiber / modified silica aerogel in Example 1 significantly improves compressive and flexural strength. Furthermore, compared to Comparative Example 3, the thermal conductivity and density of the sample in Example 1 also decrease significantly, indicating a significant improvement in thermal insulation performance. Compared to Comparative Example 2, the addition of nanoparticles to the prefabricated foam in Example 1 significantly reduces thermal conductivity and increases sound absorption, resulting in excellent overall thermal and sound insulation performance. Furthermore, the absence of a hydrophobic mixture in Example 5 significantly impacts water resistance, which in turn affects subsequent thermal insulation and durability.

[0053] The above is a preferred embodiment of the present invention. Those skilled in the art may make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A composite thermal insulation and sound insulation block, characterized in that: The mixture is prepared by mixing the following raw materials in parts by weight: 660-720 parts of cement, 210-240 parts of fly ash, 40-60 parts of fiber / modified silica aerogel, 300-350 parts of water, 4.5-10 parts of water reducer, 52-97 parts of prefabricated foam, and 40-60 parts of hydrophobic mixture; The fiber / modified silica aerogel is prepared by mixing tetraethyl orthosilicate, ethanol and deionized water, adding γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution and stirring, adjusting the pH value to acidic, ultrasonically treating, adjusting the pH value to alkaline, adding a fiber suspension, ultrasonically treating, aging, impregnating with a n-hexane / ethanol mixed solution, and freeze-drying. The fiber suspension is a plant fiber suspension, which is prepared by adding plant fibers to an ethanol solution, soaking them, and ultrasonically treating them. The prefabricated foam is prepared by mixing nano-alumina, nano-silicon dioxide and water, ultrasonically treating, adding a surfactant, and magnetically stirring to prepare a foaming liquid, and finally using an air compressor; The hydrophobic mixture is made of polydimethylsiloxane, tetraethyl orthosilicate, and dibutyltin dilaurate; The composite thermal insulation and sound insulation building block is prepared by the following preparation method: The cement, fly ash, and fiber / modified silica aerogel are mixed and stirred, and then water and polycarboxylate water reducer are added and continued to be stirred. Then, the hydrophobic mixture is added and stirred alternately at slow and fast speeds. The prefabricated foam is added and slowly stirred until completely dispersed. Then, the mixture is poured into a mold, covered with plastic wrap, allowed to stand, and demolded to obtain a composite thermal insulation and sound insulation block.

2. A composite thermal insulation and sound insulation block according to claim 1, characterized in that: The mass ratio of polydimethylsiloxane, tetraethyl orthosilicate and dibutyltin dilaurate in the hydrophobic mixture is 100:10:

1.

3. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The plant fiber suspension is prepared by adding plant fibers into an ethanol solution with a volume concentration of 30%, soaking the solution for 40 minutes, and then ultrasonically treating the solution for 15 minutes.

4. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The fiber / modified silica aerogel is prepared by mixing tetraethyl orthosilicate, ethanol and deionized water and stirring for 15-20 minutes, adding γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution and stirring for 15-20 minutes, adding hydrochloric acid to adjust the pH value to 2-3, ultrasonically treating at 20-30°C for 10-30 minutes, adding ammonia water to adjust the pH value to 7.2-8, adding fiber suspension and ultrasonically treating at 50°C for 30-50 minutes, aging for 24-36 hours, adding n-hexane / ethanol mixed solution to immerse for 6-8 hours, and freeze-drying for 24-36 hours.

5. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The mass concentration of the γ-aminoethylaminopropyltrimethoxysilane ethanol aqueous solution is 30% to 50%.

6. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The prefabricated foam is prepared by mixing nano-alumina, nano-silicon dioxide and water, ultrasonically treating for 10 to 20 minutes, adding a surfactant, and magnetically stirring at a speed of 200 rpm at room temperature for 2 to 3 hours to obtain a foaming liquid, and finally using an air compressor.

7. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The surfactant is one of sodium dodecylbenzene sulfonate, sodium polyvinyl alcohol sulfonate and sodium stearate.

8. The composite thermal insulation and sound insulation block according to claim 1, characterized in that: The composite thermal insulation and sound insulation building block is prepared by the following preparation method: Cement, fly ash, and fiber / modified silica aerogel were mixed and stirred for 2 to 5 minutes, and then water and polycarboxylate water reducer were added and stirred for 2 to 5 minutes. Then, the hydrophobic mixture was added and stirred alternately at slow and fast speeds for 2 to 5 minutes each. Prefabricated foam was added and stirred slowly until completely dispersed. Then, the mixture was poured into a mold, covered with plastic wrap, and allowed to stand at 20 to 30°C for 36 to 48 hours. The composite thermal insulation and sound insulation blocks were demoulded to obtain the composite thermal insulation and sound insulation blocks.

9. The composite thermal insulation and sound insulation building block according to claim 1, characterized in that: The plant fiber is prepared by scraping the outer layer of pineapple leaves with a manual spatula, extracting the inner fibers by combing and manual methods, rinsing with water, drying at room temperature for 36 to 48 hours, and then cutting.

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