Sound insulation wall material and preparation method thereof

Abstract

The invention provides a sound insulation wall material which comprises a porous layer, an air cavity layer and a composite cavity layer, the porous layer is a polyurethane foam composite electrostatic spinning layer, the air cavity layer is an aerogel layer with one-way orientation, the composite cavity layer is an aerogel layer with one-way orientation, and the porous layer is a polyurethane foam composite electrostatic spinning layer. Micro-nano hollow particles are loaded in the aerogel, a porous layer and a composite cavity layer are arranged on the two sides of the air cavity layer respectively, the thickness of the porous layer is 3-6 mm, the thickness of the air cavity layer is 5-8 mm, and the thickness of the composite cavity layer is 3-5 mm. The composite mode of the sound insulation wall material is a porous-resonance composite material, and the sound absorption effect on the low-frequency position is improved.

Description

Technical Field

[0001] The invention relates to the field of building materials, and in particular to a sound insulation wall material and a preparation method thereof. Background Art

[0002] Sound insulation wall is an important part of architectural acoustic design. Its main function is to absorb the sound wave energy in the room and reduce the reflection of sound waves, thereby improving the indoor acoustic environment. Sound insulation wall can effectively control the reverberation time, improve speech clarity, and reduce noise interference. It is particularly important for concert halls, theaters, conference rooms and other places. There are various types of soundproof walls (sound-absorbing walls), including single-layer sound-absorbing walls, double-layer sound-absorbing walls, composite sound-absorbing walls, etc. In terms of materials, common ones include porous sound-absorbing materials (such as mineral wool, glass wool), fiber sound-absorbing materials (such as rock wool, glass fiber), foam sound-absorbing materials (such as polyurethane foam), resonant sound-absorbing structures (such as perforated plates), etc. These materials can effectively absorb sound waves within a specific frequency range through their internal pore structure or fiber arrangement. In recent years, the research focus of sound-absorbing materials has been on improving their performance, especially in low-frequency sound absorption. Researchers have explored sound absorption systems based on acoustic metamaterials. These materials, through artificially manufactured composite periodic structures, exhibit extraordinary physical properties that traditional materials do not have, and can effectively absorb low-frequency noise. In addition, the combination of 4D printing technology allows the sound absorption frequency of acoustic metamaterials to be adaptively adjusted, improving the sound absorption capacity and flexibility. Summary of the invention

[0003] Technical problem to be solved: The purpose of the present invention is to provide a sound insulation wall material, the composite method of the sound insulation wall material used is a porous-resonance composite material, which has an improved effect on sound absorption at low frequencies.

[0004] Technical solution: A sound insulation wall material, comprising a porous layer, an air cavity layer and a composite cavity layer, wherein the porous layer is a polyurethane foam composite electrospinning layer, the air cavity layer is an aerogel layer with unidirectional orientation, the composite cavity layer is an aerogel layer with unidirectional orientation, and the aerogel is loaded with micro-nano hollow particles, and the two sides of the air cavity layer are respectively a porous layer and a composite cavity layer, wherein the thickness of the porous layer is 3-6mm, the thickness of the air cavity layer is 5-8mm, and the thickness of the composite cavity layer is 3-5mm. The preparation method of the above-mentioned sound insulation wall material comprises the following steps: S1. Preparation of the porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are mixed evenly, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, and after stirring evenly, it is poured into a mold containing an electrospinning membrane, and foamed and matured to obtain a porous layer; S2. Preparation of the air cavity layer: the straw is chopped and added to water for high-speed shearing to obtain a cellulose suspension, the suspension is poured into a mold, and unidirectional freeze-dried to obtain a directional porous material; S3. Preparation of the composite cavity layer: the straw is chopped and added to water for high-speed shearing to obtain a cellulose suspension, micro-nano hollow particles are added to the cellulose suspension, stirred evenly, the suspension is poured into a mold, and unidirectional freeze-dried to obtain a directional porous material; S4. Preparation of sound insulation wall material: Compound the porous layer, the air cavity layer and the composite cavity layer in sequence to obtain a sound insulation wall material. The electrospun membrane in step S1 is a composite spinning membrane, the thickness of the composite electrospun membrane is 1-3 mm, the porosity of the composite electrospun membrane gradually decreases with the direction of sound wave transmission, the porosity of the composite electrospun membrane on the side where the sound wave enters is 85-95%, and the porosity of the side where the sound wave exits is 60-75%. Preferably, in step S1, the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3-3.5:0.2-0.4:0.2-0.4:1-3:80-100:40-45. Preferably, in step S2, the rotation speed of the high-speed shear is 15000-18000 r / min, the time is 20-60 min, the concentration of the cellulose suspension is 1.2-1.8 wt %, the freeze-drying temperature is -30 to -20°C, and the time is 30-60 h. Preferably, in step S3, the rotation speed of the high-speed shearing is 15000-18000 r / min, the time is 20-60 min, the concentration of the cellulose suspension is 2-2.5 wt %, the freeze-drying temperature is -80 to -50°C, and the time is 30-60 h. Preferably, the micro-nano hollow particles in step S3 are hollow nanospheres coated with rare earth oxides, the hollow nanospheres are any one or more of nano TiO2, SiO2 or Al2O3, and the content of the nano hollow particles in the cellulose suspension is 2.2-2.5wt%. Preferably, the method for preparing the hollow nanospheres coated with rare earth oxide comprises the following steps: S11. The hollow nanospheres are added to an isopropanol aqueous solution, and then the pH value is adjusted to 7.5 to obtain a hollow nanosphere suspension having a concentration of 3-5 wt %; S12. Rare earth nitrate and polyvinyl pyrrolidone are added to the hollow nanosphere suspension, the mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 2-4g:1-2g:80-100mL, after stirring evenly, urea solution is added dropwise for reaction, filtered, washed and dried, and finally sintered to obtain hollow nanospheres coated with rare earth oxide. Preferably, the sintering temperature in step S12 is first calcined at 250-300° C. for 1-2 h, and then calcined at 600-650° C. for 3-5 h. Beneficial effects: The sound insulation wall material of the present invention has the following advantages: 1. The composite method of the sound insulation wall material used in the present invention is a porous-resonance composite material, which has an improved effect on the sound absorption at low frequencies. In the present invention, the porous foam and the electrostatic spinning membrane are combined, and the porosity becomes smaller and smaller along the direction of sound wave transmission, that is, the density of the electrostatic monofilament membrane increases, so that the number of fibers per unit volume increases, the number of holes constructed between the fibers increases accordingly, and the pore size decreases accordingly, resulting in an increase in the specific surface area, which increases the friction between the sound wave and the fiber surface, and is more conducive to the absorption of low-frequency sound waves; 2. The sound insulation wall material of the present invention is also compounded with an air cavity layer and a composite cavity layer. Both cavity layers are prepared by unidirectional freeze drying. The cavity layer obtained by unidirectional freeze drying is a directional parallel porous cavity layer, similar to a cavity. The air cavity layer and the composite cavity layer are of different sizes. A large amount of still air is stored inside the cavity of gradually varying sizes. After the sound waves enter the material, friction consumption is generated with the still air, which is more conducive to the absorption of the sound waves. 3. The present invention adds hollow nanospheres coated with rare earth oxides into the composite cavity layer. The rare earth elements have a special electronic structure. After being combined with porous materials, they have good vibration attenuation ability and sound absorption performance, and have a good low-frequency sound absorption effect. DETAILED DESCRIPTION The present invention will be further described below in conjunction with embodiments, which are explanations of the present invention and are not limited to the following embodiments: Example 1 Preparation of porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are evenly mixed, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3:0.2:0.2:1:80:40. After stirring evenly, pour it into a mold containing an electrospinning membrane, fix the electrospinning membrane to the bottom layer of the mold, and perform foaming and aging. The foaming temperature is 30°C, the time is 15h, the thickness of the composite electrospinning membrane is 1mm, and the porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission. The porosity of the composite electrospinning membrane on the side where the sound wave enters is 88.6%, and the porosity on the side where the sound wave goes out is 62.3%, thereby obtaining a porous layer with a thickness of 3mm. Example 2 Preparation of porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are evenly mixed, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.5:0.4:0.4:3:100:45. After stirring evenly, pour it into a mold containing an electrospinning membrane, fix the electrospinning membrane to the bottom layer of the mold, and perform foaming and aging. The foaming temperature is 20°C, the time is 30h, the thickness of the composite electrospinning membrane is 3mm, and the porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission. The porosity of the composite electrospinning membrane on the side where the sound wave enters is 92.3%, and the porosity on the side where the sound wave goes out is 68.1%, and a porous layer with a thickness of 6mm is obtained. Example 3 Preparation of porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are evenly mixed, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.2:0.3:0.3:2:95:42. After stirring evenly, pour it into a mold containing an electrospinning membrane, fix the electrospinning membrane to the bottom layer of the mold, and perform foaming and aging. The foaming temperature is 25°C, the time is 20h, the thickness of the composite electrospinning membrane is 2mm, and the porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission. The porosity of the composite electrospinning membrane on the side where the sound wave enters is 88.9%, and the porosity on the side where the sound wave goes out is 66.2%, and a porous layer with a thickness of 6mm is obtained. Example 4 Preparation of porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are evenly mixed, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.2:0.3:0.3:2:95:42. After stirring evenly, pour it into a mold containing an electrospinning membrane, fix the electrospinning membrane to the bottom layer of the mold, and perform foaming and aging. The foaming temperature is 25°C, the time is 20h, the thickness of the composite electrospinning membrane is 1mm, and the porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission. The porosity of the composite electrospinning membrane on the side where the sound wave enters is 92.8%, and the porosity on the side where the sound wave goes out is 70.2%, and a porous layer with a thickness of 6mm is obtained. Example 5 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 2.5wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -80°C for 30h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 2 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Example 6 The difference between Example 6 and Example 5 is that the thickness of the directionally arranged porous material in step S1 is 6 mm. Example 7 The difference between Example 7 and Example 5 is that the thickness of the directionally arranged porous material in step S1 is 7 mm. Example 8 The difference between Example 8 and Example 5 is that the thickness of the directionally arranged porous material in step S1 is 8 mm. Example 9 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 18000r / min for 20min to obtain a cellulose suspension with a concentration of 1.8wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -30°C for 30h to obtain a directional porous material with a thickness of 7mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 18000r / min for 20min to obtain a cellulose suspension with a concentration of 2wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.5wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -50°C for 60h to obtain a directional porous material with a thickness of 3mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 1 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Example 10 The difference between Example 10 and Example 9 is that the thickness of the directionally arranged porous material in step S2 is 4 mm. Embodiment 11 The difference between Example 11 and Example 9 is that the thickness of the directionally arranged porous material in step S2 is 5 mm. Example 12 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 2.5wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -80°C for 30h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 1 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Example 13 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 2.5wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -80°C for 30h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 3 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Embodiment 14 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 2.5wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -80°C for 30h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 4 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Comparative Example 1 The difference between Comparative Example 1 and Example 5 is that the thickness of the directionally arranged porous material in step S1 is 3 mm. Comparative Example 2 The difference between Comparative Example 1 and Example 5 is that the thickness of the directionally arranged porous material in step S1 is 10 mm. Sound absorption and energy absorption tests: The following sound absorption performance tests were carried out in accordance with GB / T 18696.2-2002. Comparative Example 3 The difference between Comparative Example 3 and Example 9 is that the thickness of the directionally arranged porous material in step S2 is 2 mm. Comparative Example 4 The difference between Comparative Example 4 and Example 9 is that the thickness of the directionally arranged porous material in step S2 is 7 mm. Low frequency maximum sound absorption coefficient Low frequency average sound absorption coefficient Example 9 0.910 0.409 Example 10 0.923 0.412 Embodiment 11 0.915 0.408 Comparative Example 3 0.815 0.356 Comparative Example 4 0.905 0.388 Comparative Example 5 The difference between Comparative Example 5 and Example 12 is that the porous layer is prepared in the following manner: After mixing water, triethylenediamine, dibutyltin dilaurate and silicone oil evenly, add polyether polyol N330. After mixing evenly, add diphenylmethane diisocyanate, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.2:0.3:0.3:2:95:42. After stirring evenly, pour into a mold for foaming and aging at a foaming temperature of 25°C for 20 hours to obtain a porous layer with a thickness of 6 mm. Comparative Example 6 The difference between Comparative Example 6 and Example 12 is that the porosity of the electrospun membrane in the porous layer remains unchanged, and an electrospun membrane with uniform porosity is used: After mixing water, triethylenediamine, dibutyltin dilaurate and silicone oil evenly, add polyether polyol N330. After mixing evenly, add diphenylmethane diisocyanate, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.2:0.3:0.3:2:95:42. After stirring evenly, pour it into a mold containing an electrospinning membrane for foaming and aging. The foaming temperature is 25°C and the time is 20 hours. The thickness of the electrospinning membrane is 2 mm, and the porosity of the electrospinning membrane is 88.9%. A porous layer with a thickness of 6 mm is obtained. Low frequency maximum sound absorption coefficient Low frequency average sound absorption coefficient Example 12 0.909 0.401 Example 13 0.921 0.412 Embodiment 14 0.915 0.410 Comparative Example 5 0.812 0.355 Comparative Example 6 0.884 0.400 Comparative Example 7 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 16000 r / min for 40 min to obtain a cellulose suspension with a concentration of 1.5 wt%. The suspension was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60 h to obtain a directional porous material with a thickness of 6 mm. S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 16000r / min for 40min to obtain a cellulose suspension with a concentration of 2.5wt%, and hollow nano-SiO2 particles were added to the cellulose suspension. The content of the hollow nano-SiO2 particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and subjected to unidirectional freeze drying at a freeze drying temperature of -80°C for 60h to obtain a directional porous material with a thickness of 5mm. S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 1 are compounded in sequence to obtain a sound insulation wall material. Comparative Example 8 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of sound insulation wall material: The porous layer and the air cavity layer prepared in Example 2 are compounded to obtain a sound insulation wall material. Comparative Example 9 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000 r / min for 60 min to obtain a cellulose suspension with a concentration of 2.5 wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2 wt%, and after stirring evenly, the suspension was poured into a mold and subjected to unidirectional freeze drying at a freeze drying temperature of -80 ° C for 30 h to obtain a directional porous material with a thickness of 5 mm; S2. Preparation of sound insulation wall material: The porous layer and the composite cavity layer prepared in Example 2 are compounded in sequence to obtain a sound insulation wall material; The method for preparing the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Comparative Example 10 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are mixed evenly, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, wherein the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3.5:0.4:0.4:3:100:45. After stirring evenly, pour it into a mold containing an electrospinning membrane, fix the electrospinning membrane to the bottom layer of the mold, and perform foaming and aging. The foaming temperature is 20°C and the time is 30 hours. The thickness of the composite electrospinning membrane is 3 mm. The porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission. The porosity of the composite electrospinning membrane on the side where the sound wave enters is 92.3%, and the porosity on the side where the sound wave exits is 68.1%, thereby obtaining a porous layer with a thickness of 3 mm. S2. Preparation of air cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 2.5wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -80°C for 30h to obtain a directional porous material with a thickness of 5mm; S4. Preparation of sound insulation wall material: Compounding the porous layer, the air cavity layer and the composite cavity layer in sequence to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Comparative Example 11 A method for preparing a sound insulation wall material, the method comprising the following steps: S1. Preparation of air cavity layer: the straw was chopped and added into water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, which was poured into a mold and subjected to unidirectional freeze drying at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S2. Preparation of the composite cavity layer: the straw was chopped and added to water for high-speed shearing at a speed of 15000r / min for 60min to obtain a cellulose suspension with a concentration of 1.2wt%, micro-nano hollow particles were added to the cellulose suspension, and the content of the micro-nano hollow particles in the cellulose suspension was 2.2wt%. After stirring, the suspension was poured into a mold and unidirectionally freeze-dried at a temperature of -20°C for 60h to obtain a directional porous material with a thickness of 5mm; S3. Preparation of sound insulation wall material: The porous layer, air cavity layer and composite cavity layer prepared in Example 2 are compounded in sequence. When the porous layer and the air cavity layer are compounded, the side containing the electrospinning membrane is compounded with the air cavity layer to obtain a sound insulation wall material; wherein the preparation method of the micro-nano hollow particles comprises the following steps: S11. The SiO2 hollow nanospheres were added to an isopropanol aqueous solution, and then the pH value was adjusted to 7.5 to obtain a 4 wt% hollow nanosphere suspension; S12. Add cerium nitrate and polyvinyl pyrrolidone to the hollow nanosphere suspension. The mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 3g:1.5g:90mL. After stirring evenly, add urea solution to react, filter, wash and dry, and finally sinter. The sintering temperature is first calcined at 300°C for 1h, and then calcined at 600°C for 5h to obtain hollow SiO2 nanospheres coated with cerium oxide. Low frequency maximum sound absorption coefficient Low frequency average sound absorption coefficient Comparative Example 7 0.874 0.388 Comparative Example 8 0.659 0.256 Comparative Example 9 0.754 0.315 Comparative Example 10 0.858 0.375 Comparative Example 11 0.874 0.391 Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A sound insulation wall material, characterized in that: The sound insulation wall material comprises a porous layer, an air cavity layer and a composite cavity layer, wherein the porous layer is a polyurethane foam composite electrospinning layer, the air cavity layer is an aerogel layer with unidirectional orientation, the composite cavity layer is an aerogel layer with unidirectional orientation, and the aerogel is loaded with micro-nano hollow particles, and the two sides of the air cavity layer are respectively a porous layer and a composite cavity layer, wherein the thickness of the porous layer is 3-6 mm, the thickness of the air cavity layer is 5-8 mm, and the thickness of the composite cavity layer is 3-5 mm.

2. The method for preparing the sound insulation wall material according to claim 1, characterized in that: The preparation method comprises the following steps: S1. Preparation of the porous layer: After water, triethylenediamine, dibutyltin dilaurate and silicone oil are mixed evenly, polyether polyol N330 is added, and after mixing evenly, diphenylmethane diisocyanate is added, and after stirring evenly, it is poured into a mold containing an electrospinning membrane, and foamed and matured to obtain a porous layer; S2. Preparation of the air cavity layer: the straw is chopped and added to water for high-speed shearing to obtain a cellulose suspension, the suspension is poured into a mold, and unidirectional freeze-dried to obtain a directional porous material; S3. Preparation of the composite cavity layer: the straw is chopped and added to water for high-speed shearing to obtain a cellulose suspension, micro-nano hollow particles are added to the cellulose suspension, stirred evenly, the suspension is poured into a mold, and unidirectional freeze-dried to obtain a directional porous material; S4. Preparation of sound insulation wall material: Compound the porous layer, the air cavity layer and the composite cavity layer in sequence to obtain the sound insulation wall material.

3. The method for preparing the sound insulation wall material according to claim 2, characterized in that: The electrospinning membrane in step S1 is a composite spinning membrane, the thickness of the composite electrospinning membrane is 1-3 mm, the porosity of the composite electrospinning membrane gradually decreases with the direction of sound wave transmission, the porosity of the composite electrospinning membrane on the side where the sound wave enters is 85-95%, and the porosity of the side where the sound wave exits is 60-75%.

4. The method for preparing the sound insulation wall material according to claim 2, characterized in that: In the step S1, the mass ratio of water, triethylenediamine, dibutyltin dilaurate, silicone oil, polyether polyol N330 and diphenylmethane diisocyanate is 3-3.5:0.2-0.4:0.2-0.4:1-3:80-100:40-45.

5. The method for preparing the sound insulation wall material according to claim 2, characterized in that: In step S2, the rotation speed of the high-speed shearing is 15000-18000 r / min, the time is 20-60 min, the concentration of the cellulose suspension is 1.2-1.8 wt %, the freeze-drying temperature is -30 to -20° C., and the time is 30-60 h.

6. The method for preparing the sound insulation wall material according to claim 2, characterized in that: In step S3, the rotation speed of the high-speed shearing is 15000-18000 r / min, the time is 20-60 min, the concentration of the cellulose suspension is 2-2.5 wt %, the freeze-drying temperature is -80 to -50° C., and the time is 30-60 h.

7. The method for preparing the sound insulation wall material according to claim 6, characterized in that: The micro-nano hollow particles in step S3 are hollow nanospheres coated with rare earth oxides, the hollow nanospheres are any one or more of nano TiO2, SiO2 or Al2O3, and the content of the nano hollow particles in the cellulose suspension is 2.2-2.5wt%.

8. The method for preparing the sound insulation wall material according to claim 7, characterized in that: The method for preparing the hollow nanospheres coated with rare earth oxide comprises the following steps: S11. The hollow nanospheres are added to an isopropanol aqueous solution, and then the pH value is adjusted to 7.5 to obtain a hollow nanosphere suspension having a concentration of 3-5 wt %; S12. Rare earth nitrate and polyvinyl pyrrolidone are added to the hollow nanosphere suspension, the mass volume ratio of rare earth nitrate, polyvinyl pyrrolidone and hollow nanosphere suspension is 2-4g:1-2g:80-100mL, after stirring evenly, urea solution is added dropwise for reaction, filtered, washed and dried, and finally sintered to obtain hollow nanospheres coated with rare earth oxide.

9. The method for preparing the sound insulation wall material according to claim 8, characterized in that: The sintering temperature in step S12 is first calcined at 250-300° C. for 1-2 hours, and then calcined at 600-650° C. for 3-5 hours.

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