Aluminum fiber sound absorbing panel

Abstract

The application discloses an aluminum fiber sound absorption board and belongs to the technical field of sound absorption boards. The sound absorption board comprises the following raw materials in parts by weight: 45-50 parts of polyether polyol, 40-45 parts of isocyanate, 15-20 parts of aluminum powder, 12-18 parts of chopped glass fiber, 12-16 parts of flame retardant, 0.5-0.8 parts of coupling agent, 2-4 parts of antibacterial additive, 3-5 parts of foaming agent, 0.8-1.2 parts of foam stabilizer, 0.5-0.7 parts of catalyst and 0.2-0.3 parts of dispersing agent. The antibacterial additive is prepared by composite modification of chloramine, pyridine quaternary ammonium salt and chitosan, and has a triple synergistic antibacterial mechanism. The aluminum powder and the glass fiber are used to construct a stable porous structure, so that the sound absorption performance and the mechanical strength are improved; the antibacterial component is combined with the material body through a covalent bond and does not precipitate for a long time. The sound absorption board has excellent sound absorption, antibacterial and mechanical properties and is suitable for places with high requirements for health and sound quality, such as hospitals and clean workshops.

Description

Technical Field

[0001] This invention belongs to the field of sound-absorbing panel technology, specifically, it relates to an aluminum fiber sound-absorbing panel. Background Technology

[0002] In the current field of building decoration materials, especially with the increasing requirements for indoor environmental sound quality, hygiene and safety, and environmental protection performance, sound-absorbing panels, as an important functional material, are widely used in hospitals, schools, rail transit, clean rooms, office buildings, and public buildings.

[0003] Traditional sound-absorbing panels typically use materials like polyurethane foam as the matrix, relying on their porous structure to absorb and attenuate sound waves. However, these panels, based solely on organic polymers, have several inherent drawbacks in practical use. For example, while polyurethane has good processing performance and mature molding technology, it lacks antibacterial properties, and its surface and internal pores easily become breeding grounds for bacteria, mold, and other microorganisms. In humid or poorly ventilated environments, such as hospital wards, underground spaces, and air conditioning return air ducts, the surface and interior of the sound-absorbing panels easily absorb dust, sebum, bodily fluids, and other organic pollutants, further promoting bacterial growth, especially common pathogens such as Escherichia coli, Staphylococcus aureus, and Candida albicans. This not only affects the normal performance of the material but also poses a potential threat to human health.

[0004] Finally, during the foaming of a single organic matrix material, the cell walls are prone to rupture under surface tension, leading to pore structure collapse. The merging of large pores actually reduces the specific surface area and sound absorption efficiency. Therefore, it is urgent to solve these problems to meet the higher technical requirements of the sound-absorbing panel technology field. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an aluminum fiber sound-absorbing panel.

[0006] The objective of this invention can be achieved through the following technical solutions: An aluminum fiber sound-absorbing panel comprises the following raw materials in parts by weight: 45-50 parts polyether polyol, 40-45 parts isocyanate, 15-20 parts aluminum powder, 12-18 parts chopped glass fiber, 12-16 parts flame retardant, 0.5-0.8 parts coupling agent, 2-4 parts antibacterial additive, 3-5 parts foaming agent, 0.8-1.2 parts foam stabilizer, 0.5-0.7 parts catalyst, and 0.2-0.3 parts dispersant.

[0007] Aluminum powder and glass fiber (i.e. "aluminum fiber") are added to the raw materials. Aluminum powder, as a rigid filler, is dispersed in the matrix, which not only improves the surface hardness and scratch resistance of the sound-absorbing panel, but also increases the roughness of the pore walls, enhances the diffuse reflection of mid-to-high frequency sound waves, and assists in sound absorption. Glass fiber not only improves the strength of the sound-absorbing panel and provides porous channels, but also prevents the pores from collapsing and maintains structural stability.

[0008] As a further technical solution, the flame retardant is a composite flame retardant of aluminum hydroxide and DOPO, with a weight ratio of 3:1.

[0009] As a further technical solution, the coupling agent is a silane coupling agent.

[0010] As a further technical solution, the antibacterial additive is prepared through the following steps: Step A1: Add cyanuric acid, anhydrous potassium carbonate, potassium iodide and N,N-dimethylformamide sequentially to a flask, install a reflux condenser, turn on the magnetic stirrer, and heat to 80-85℃. Keep the temperature and stir for 20-30 minutes, then add 1,4-dichlorobutane dropwise. After the addition is complete, keep the reaction temperature for 5-6 hours. The reaction is complete, and product A is obtained. Step A2: Add product A and deionized water to the flask, turn on the magnetic stirrer, then add sodium hydroxide solution (0.1M) dropwise to adjust the pH to 10-11. Cool the reaction system to 0-5℃ in an ice-water bath, then add sodium hypochlorite solution (5% by mass). After the addition is complete, remove the ice bath and allow the temperature to rise naturally to room temperature (20-25℃). Continue stirring for 2-3 hours until the reaction is complete, and product B is obtained. Step A3: Add product B, 3-pyridinecarboxaldehyde and acetonitrile to the flask in sequence, install the reflux condenser, turn on the magnetic stirrer, heat the oil bath to 82-85℃, and reflux and stir for 10-12 hours. When the reaction is complete, product C is obtained. Step A4: Dissolve chitosan in acetic acid solution (1% by mass) in a flask, then mix product C with N,N-dimethylformamide and add it to the flask. Then stir the reaction at room temperature (20-25℃) for 12-24 hours until the reaction is complete, and obtain the antibacterial additive.

[0011] As a further technical solution, the ratio of cyanuric acid to 1,4-dichlorobutane in step A1 is 12.9g:13.3-13.9g.

[0012] As a further technical solution, the ratio of product A to sodium hypochlorite solution in step A2 is 21.9g:16-20mL.

[0013] As a further technical solution, the ratio of product B to 3-pyridinecarboxaldehyde in step A3 is 12.9g:13.3-13.9g.

[0014] As a further technical solution, the ratio of chitosan to product C in step A4 is 10g:6.6g.

[0015] In the preparation process of the above antibacterial additive, the reaction formulas for steps A1, A2, and A3 are as follows: This invention prepares product C and then modifies chitosan to obtain an antibacterial additive. The antibacterial additive contains three antibacterial components. The chloramine groups slowly release active chlorine upon contact with microorganisms, oxidizing enzymes and proteins on the bacterial cell membrane, leading to cell death. The quaternary ammonium nitrogen of the pyridine quaternary ammonium salt carries a permanently positive charge and electrostatically adsorbs the negatively charged bacterial cell membrane, disrupting membrane integrity and causing leakage of contents. Chitosan is a natural antibacterial agent. The three antibacterial components work synergistically, significantly improving the antibacterial performance of the material. Furthermore, the chitosan molecule contains a large number of amino groups, which can react with isocyanate (MDI) in polyurethane raw materials to form a covalent cross-linked network, making the antibacterial additive an integral part of the material, preventing precipitation, and reducing performance degradation caused by uneven dispersion. Simultaneously, chitosan itself is environmentally friendly and partially biodegradable.

[0016] The beneficial effects of this invention are: 1. The self-made antibacterial additive of this invention can improve the antibacterial properties of the sound-absorbing panel and is covalently bonded to the material body, and does not precipitate out for a long time; 2. Adding aluminum powder and glass fiber not only improves the sound absorption capacity of the sound-absorbing panel, but also enhances its mechanical strength. 3. Chitosan in the antibacterial additive is a natural polysaccharide that can be partially biodegraded, reducing the environmental impact after disposal; In summary, this invention has outstanding advantages in antibacterial properties, sound absorption, and mechanical properties, and has important application value in the field of sound-absorbing panel technology. Detailed Implementation

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 Preparation of antibacterial additives: Step A1: In a flask, add 25.8 g of cyanuric acid, 55.2 g of anhydrous potassium carbonate, 3.4 g of potassium iodide, and 200 mL of N,N-dimethylformamide in sequence. Install a reflux condenser, turn on the magnetic stirrer, and heat to 80 °C. Keep the temperature and stir for 20 min. Then add 26.6 g of 1,4-dichlorobutane dropwise. After the addition is complete, keep the reaction temperature for 5 h. When the reaction is complete, cool naturally to room temperature, filter, remove N,N-dimethylformamide by vacuum distillation, and purify by column chromatography to obtain product A. Step A2: Add 32.9g of product A and 150mL of deionized water to a flask, turn on the magnetic stirrer, then add sodium hydroxide solution (0.1M) dropwise to adjust the pH to 10. Cool the reaction system to 0-5℃ in an ice-water bath, then add 24mL of sodium hypochlorite solution (5% by mass). After the addition is complete, remove the ice bath and allow the temperature to rise naturally to room temperature (25℃). Continue stirring for 2 hours until the reaction is complete. Purify the product B by rotary evaporation under reduced pressure and column chromatography. Step A3: Add 12.9g of product B, 13.3g of 3-pyridinecarboxaldehyde and 100mL of acetonitrile to the flask in sequence, install the reflux condenser, turn on the magnetic stirrer, heat the oil bath to 82℃, and reflux and stir for 10h. After the reaction is complete, cool the reaction solution to room temperature, and purify it by rotary evaporation under reduced pressure and column chromatography to obtain product C. Step A4: Dissolve 10g of chitosan in 100mL of acetic acid solution (1% by mass) in a flask. Then, mix 6.6g of product C with 50mL of N,N-dimethylformamide and add the mixture to the flask. Stir the mixture at room temperature (25℃) for 12 hours until the reaction is complete. After post-processing, the antibacterial additive is obtained.

[0019] An aluminum fiber sound-absorbing panel is prepared by the following steps: Step 1: Immerse 12 parts of chopped glass fibers (5 mm in length and 10 μm in diameter) in an ethanol / water (9:1) solution containing 0.5 parts of silane coupling agent (KH-550), stir for 10 min, remove and dry in an oven at 80 °C for 1 h; then dry 15 parts of aluminum powder (200 mesh, spherical) in an oven at 105 °C for 2 h to remove surface adsorbed moisture, and obtain the treated glass fibers and aluminum powder; Step 2: Add 45 parts of polyether polyol to a high-speed disperser, heat to 40°C, and add 12 parts of flame retardant (aluminum hydroxide and DOPO composite flame retardant, with a weight ratio of 3:1), 2 parts of antibacterial additive and 0.2 parts of dispersant (BYK-P104) in sequence while stirring at 500 rpm. Then increase the speed to 1200 rpm and stir for 15 minutes. Step 3: Reduce the speed to 600 rpm, add the treated glass fiber and aluminum powder, stir for 10 minutes until the fiber and aluminum powder are completely dispersed, and finally add 3 parts foaming agent (water) and 0.8 parts foam stabilizer (silicone oil L-580), stir for 5 minutes to obtain polyol premix; Step 4: First, mix 40 parts of isocyanate (MDI) and 0.5 parts of triethylenediamine evenly, then pour it into the polyol premix. Immediately afterward, stir with a high-speed mixer at 2000 rpm for 5 seconds, then pour it into a mold preheated to 45°C. After closing the mold, keep it at 45°C. After free foaming, keep the mold temperature at 50°C and continue curing for 10 minutes. Open the mold and take out the sound-absorbing board. Then, place the sound-absorbing board in an 80°C oven for 2 hours to obtain the aluminum fiber sound-absorbing board.

[0020] Example 2 Preparation of antibacterial additives: Step A1: In a flask, add 25.8 g of cyanuric acid, 55.2 g of anhydrous potassium carbonate, 3.4 g of potassium iodide, and 200 mL of N,N-dimethylformamide in sequence. Install a reflux condenser, turn on the magnetic stirrer, and heat to 80-85℃. Maintain the temperature and stir for 30 min. Then add 27.8 g of 1,4-dichlorobutane dropwise. After the addition is complete, maintain the temperature for 6 h. When the reaction is complete, allow it to cool naturally to room temperature, filter, remove N,N-dimethylformamide by vacuum distillation, and purify by column chromatography to obtain product A. Step A2: Add 32.9g of product A and 150mL of deionized water to a flask, turn on the magnetic stirrer, then add sodium hydroxide solution (0.1M) dropwise to adjust the pH to 10. Cool the reaction system to 0-5℃ in an ice-water bath, then add 30mL of sodium hypochlorite solution (5% by mass). After the addition is complete, remove the ice bath and allow the temperature to rise naturally to room temperature (25℃). Continue stirring for 3 hours until the reaction is complete. Purify the product B by rotary evaporation under reduced pressure and column chromatography. Step A3: Add 12.9g of product B, 13.9g of 3-pyridinecarboxaldehyde and 100mL of acetonitrile to the flask in sequence, install the reflux condenser, turn on the magnetic stirrer, heat the oil bath to 85℃, and reflux and stir for 12h. After the reaction is complete, cool the reaction solution to room temperature, and purify it by rotary evaporation under reduced pressure and column chromatography to obtain product C. Step A4: Dissolve 10g of chitosan in 100mL of acetic acid solution (1% by mass) in a flask. Then, mix 6.6g of product C with 50mL of N,N-dimethylformamide and add the mixture to the flask. Stir the mixture at room temperature (25℃) for 24 hours until the reaction is complete. After post-processing, the antibacterial additive is obtained.

[0021] An aluminum fiber sound-absorbing panel is prepared by the following steps: Step 1: Immerse 15 parts of chopped glass fibers (5 mm in length and 10 μm in diameter) in an ethanol / water (9:1) solution containing 0.6 parts of silane coupling agent (KH-550), stir for 10 min, remove and dry in an oven at 80 °C for 1 h; then dry 17.5 parts of aluminum powder (200 mesh, spherical) in an oven at 105 °C for 2 h to remove surface adsorbed moisture, and obtain the treated glass fibers and aluminum powder; Step 2: Add 50 parts of polyether polyol to a high-speed disperser, heat to 50°C, and add 14 parts of flame retardant (aluminum hydroxide and DOPO composite flame retardant, with a weight ratio of 3:1), 3 parts of antibacterial additive and 0.3 parts of dispersant (BYK-P104) in sequence while stirring at 500 rpm. Then increase the speed to 1200 rpm and stir for 15 minutes. Step 3: Reduce the speed to 600 rpm, add the treated glass fiber and aluminum powder, stir for 10 minutes until the fiber and aluminum powder are completely dispersed, and finally add 4 parts of foaming agent (water) and 1.0 part of foam stabilizer (silicone oil L-580), stir for 5 minutes to obtain polyol premix; Step 4: First, mix 45 parts of isocyanate (MDI) and 0.7 parts of triethylenediamine evenly, then pour it into the polyol premix. Immediately afterward, stir with a high-speed mixer at 2000 rpm for 8 seconds, then pour it into a mold preheated to 45°C. After closing the mold, keep the mold at 45-50°C. After free foaming, keep the mold temperature at 50°C and continue curing for 10-15 minutes. Open the mold and take out the sound-absorbing board. Then, place the sound-absorbing board in an 80°C oven for 2 hours to obtain the aluminum fiber sound-absorbing board.

[0022] Example 3 The only difference between this embodiment and Embodiment 2 is that, in this embodiment, an aluminum fiber sound-absorbing panel is prepared through the following steps: Step 1: Immerse 18 parts of chopped glass fibers (5 mm in length and 10 μm in diameter) in an ethanol / water (9:1) solution containing 0.8 parts of silane coupling agent (KH-550), stir for 10 min, remove and dry in an oven at 80 °C for 1 h; then dry 20 parts of aluminum powder (200 mesh, spherical) in an oven at 105 °C for 2 h to remove surface adsorbed moisture, and obtain the treated glass fibers and aluminum powder; Step 2: Add 50 parts of polyether polyol to a high-speed disperser, heat to 50°C, and add 16 parts of flame retardant (aluminum hydroxide and DOPO composite flame retardant, with a weight ratio of 3:1), 4 parts of antibacterial additive and 0.3 parts of dispersant (BYK-P104) in sequence while stirring at 500 rpm. Then increase the speed to 1200 rpm and stir for 15 minutes. Step 3: Reduce the speed to 600 rpm, add the treated glass fiber and aluminum powder, stir for 10 minutes until the fiber and aluminum powder are completely dispersed, and finally add 5 parts of foaming agent (water) and 1.2 parts of foam stabilizer (silicone oil L-580), stir for 5 minutes to obtain polyol premix; Step 4: First, mix 45 parts of isocyanate (MDI) and 0.7 parts of triethylenediamine evenly, then pour it into the polyol premix. Immediately afterward, stir with a high-speed mixer at 2000 rpm for 8 seconds, then pour it into a mold preheated to 45°C. After closing the mold, keep the mold at 50°C. After free foaming, keep the mold temperature at 50°C and continue curing for 15 minutes. Open the mold and take out the sound-absorbing board. Then, place the sound-absorbing board in an 80°C oven for 2 hours to obtain the aluminum fiber sound-absorbing board.

[0023] Comparative Example 1 This comparative example uses the same preparation method as Example 3, except that the antibacterial additive in the raw materials is replaced with an equal amount of unmodified ordinary chitosan.

[0024] Comparative Example 2 This comparative example uses the same preparation method as Example 3, the only difference being that chopped glass fibers and aluminum powder are not added to the raw materials.

[0025] Examples 1, 2, and 3, and Comparative Examples 1 and 2, were measured according to the following standards; Using the GB / T 20247-2006 standard, the sound absorption coefficient of the sample at different frequencies (250Hz, 500Hz, 1000Hz, 2000Hz) was determined, and the average value of the four frequencies was calculated. The compressive strength of the specimens was determined according to GB / T 8813-2020 standard; The antibacterial properties of the samples were determined according to GB / T 31402-2015 standard. The performance results measured according to the above standards are shown in Table 1: Table 1 As can be seen from the performance test results in Table 1, the sound-absorbing panels prepared in Examples 1, 2 and 3 of the present invention have significantly improved sound absorption and mechanical properties compared with Comparative Example 2 due to the addition of aluminum fiber. Furthermore, the self-made antibacterial additive has significant antibacterial properties. Therefore, the present invention has important application value in the field of sound-absorbing panel technology.

[0026] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. An aluminum fiber sound-absorbing panel, characterized in that, The raw materials include the following parts by weight: 45-50 parts polyether polyol, 40-45 parts isocyanate, 15-20 parts aluminum powder, 12-18 parts chopped glass fiber, 12-16 parts flame retardant, 0.5-0.8 parts coupling agent, 2-4 parts antibacterial additive, 3-5 parts foaming agent, 0.8-1.2 parts foam stabilizer, 0.5-0.7 parts catalyst and 0.2-0.3 parts dispersant.

2. The aluminum fiber sound-absorbing panel according to claim 1, characterized in that, The antibacterial additive is prepared by the following steps: Step A1: Add cyanuric acid, anhydrous potassium carbonate, potassium iodide and N,N-dimethylformamide to a flask in sequence, start stirring, heat to 80-85℃, keep warm and stir for 20-30 min, then add 1,4-dichlorobutane dropwise. After the addition is complete, keep the reaction at the temperature for 5-6 h. The reaction is complete, and product A is obtained. Step A2: Add product A and deionized water to the flask, turn on the magnetic stirrer, then add sodium hydroxide solution dropwise to adjust the pH to 10-11, cool to 0-5℃ in an ice-water bath, then add sodium hypochlorite solution dropwise. After the addition is complete, remove the ice bath, raise the temperature to room temperature, and continue the reaction for 2-3 hours. The reaction is complete, and product B is obtained. Step A3: Add product B, 3-pyridinecarboxaldehyde and acetonitrile to the flask in sequence, start stirring, heat to 82-85℃, reflux and stir for 10-12 hours until the reaction is complete, and obtain product C. Step A4: Dissolve chitosan in acetic acid solution in a flask, then mix product C with N,N-dimethylformamide and add it to the flask. Then stir the mixture at room temperature for 12-24 hours until the reaction is complete, and obtain the antibacterial additive.

3. The aluminum fiber sound-absorbing panel according to claim 2, characterized in that, In step A1, the ratio of cyanuric acid to 1,4-dichlorobutane is 12.9 g: 13.3-13.9 g.

4. The aluminum fiber sound-absorbing panel according to claim 2, characterized in that, In step A2, the ratio of product A to sodium hypochlorite solution is 21.9 g: 16-20 mL.

5. The aluminum fiber sound-absorbing panel according to claim 2, characterized in that, In step A3, the ratio of product B to 3-pyridinecarboxaldehyde is 12.9 g: 13.3-13.9 g.

6. The aluminum fiber sound-absorbing panel according to claim 2, characterized in that, In step A4, the ratio of chitosan to product C is 10g:6.6g.

7. The aluminum fiber sound-absorbing panel according to claim 1, characterized in that, The flame retardant is a composite flame retardant of aluminum hydroxide and DOPO, with a weight ratio of 3:

1.

8. The aluminum fiber sound-absorbing panel according to claim 1, characterized in that, The coupling agent is a silane coupling agent.

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