Glass fiber aluminum foil composite sound insulation material and preparation method thereof

Abstract

The application discloses a kind of glass fiber aluminum foil composite sound insulation material and preparation method thereof, belong to sound insulation material technical field.The sound insulation material includes upper layer and lower layer, the material of upper layer is aluminum foil composite glass fiber cloth, the material of lower layer includes polyether polyol, isocyanate, flame retardant, anti-aging additive, water, foam stabilizer and catalyst.Among them, anti-aging additive is prepared by the reaction of melamine and phenyl isothiocyanate and then with 3-hydroxypropionic acid, lower layer material foams in the mold with hemispherical protrusions, and the surface forms sound absorption groove.The upper layer and the lower layer are bonded by moisture-cured polyurethane hot melt adhesive.The application forms a "mass-spring" structure by aluminum foil and polyurethane foam, significantly improves the low-frequency sound insulation effect;The mechanical strength and wear resistance of glass fiber cloth and aluminum foil reinforcing material;Anti-aging additive gives the material excellent long-term anti-aging performance.

Description

Technical Field

[0001] This invention belongs to the field of sound insulation materials technology, specifically, it relates to a fiberglass aluminum foil composite sound insulation material and its preparation method. Background Technology

[0002] With the acceleration of urbanization and the rapid development of industry and transportation, noise pollution has become one of the core issues affecting the living environment and public health. As the core carrier of noise control, the performance of sound insulation materials directly determines the effectiveness of noise control.

[0003] Currently, commonly used sound insulation materials are mainly single porous materials, such as polyurethane foam. Polyurethane foam is one of the most commonly used matrix materials in the sound insulation field due to its low density, adjustable open-cell ratio, ease of processing and molding, and certain sound absorption and insulation capabilities. However, existing polyurethane foam materials have significant shortcomings when used directly as a sound insulation layer.

[0004] First, the sound insulation performance of polyurethane foam mainly relies on the frictional dissipation of sound waves through its internal porous structure. However, in the existing manufacturing process, it is difficult to precisely control the foam cell size, porosity, and connectivity. This often results in uneven cell distribution, excessively large or small pore size, and poor connectivity, which allows sound waves, especially low-frequency sound waves, to easily penetrate the foam and fail to achieve effective absorption and blocking. Consequently, the overall low-frequency sound insulation effect of polyurethane foam material is greatly reduced, making it difficult to cope with low-frequency noise pollution generated by traffic noise, equipment operation, etc.

[0005] Secondly, polyurethane foam, being an organic polymer material, has limited anti-aging properties. With prolonged use, exposure to high temperatures and oxygen can cause yellowing and powdering, leading to pore structure collapse and a rapid decline in acoustic performance. Finally, polyurethane foam has low surface strength and poor abrasion resistance, easily producing debris when subjected to scratches, airflow erosion, or repeated compression. This not only pollutes the environment but also weakens its structural integrity for long-term use. In conclusion, it is urgent to address these issues to meet the higher technical demands of the sound insulation materials field. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a fiberglass aluminum foil composite sound insulation material and its preparation method.

[0007] The objective of this invention can be achieved through the following technical solutions: A fiberglass aluminum foil composite sound insulation material, comprising an upper layer and a lower layer.

[0008] Preferably, the material of the upper layer is aluminum foil composite glass fiber cloth.

[0009] Preferably, the thickness of the aluminum foil composite glass fiber cloth is 7-9 μm.

[0010] Preferably, the material of the lower layer comprises the following raw materials in parts by weight: 45-55 parts polyether polyol, 35-42 parts isocyanate, 8-10 parts flame retardant, 2-4 parts anti-aging additive, 2-3 parts water, 1.5-2.5 parts foam stabilizer and 0.5-0.7 parts catalyst.

[0011] Preferably, the upper and lower layers are bonded together with hot melt adhesive.

[0012] Preferably, the hot melt adhesive is a moisture-curing polyurethane hot melt adhesive.

[0013] Preferably, the lower layer material is prepared by the following steps: A1. Disperse the polyether polyol, flame retardant, anti-aging additive, water, foam stabilizer and catalyst in a stirred tank (1200rpm-1500rpm) for 5-10min according to the formula to obtain white material; A2. Continue to add isocyanate to the mixing vessel, stir rapidly (1800rpm-2000rpm) for 10s, pour into the mold (preheated to 45-50℃), close and lock the mold, keep the mold temperature at 50-55℃, allow it to foam freely for 3-5 minutes. During the foaming process, the foam will wrap around the conical protrusions. After curing, demolding will form sound-absorbing grooves on the foam surface. Then let it stand and mature for 12-24 hours, and finally heat treat it in an oven (120℃) for 1-2 hours to obtain the lower layer material.

[0014] Preferably, the mold base plate is provided with an array of hemispherical protrusions with a diameter of 15mm.

[0015] Preferably, the anti-aging additive is prepared by the following steps: B1. Melamine and anhydrous pyridine are added to a three-necked round-bottom flask (equipped with a condenser) at room temperature. Then, the oil bath temperature is raised to 100-105℃, and the mixture is stirred to dissolve the melamine. Then, dibutyltin dilaurate (catalyst) and phenyl isothiocyanate are added. The mixture is kept at this temperature for 2-3 hours. After the reaction is completed, the intermediate product of the anti-aging additive is obtained through post-treatment. B2. At room temperature, 3-hydroxypropionic acid and anhydrous N,N-dimethylformamide are added to a flask and stirred until homogeneous. Then, N-hydroxysuccinimide and EDC·HCl are added and stirred until homogeneous. Finally, the intermediate product of the anti-aging additive is added and the mixture is stirred at room temperature for 12-16 hours until the reaction is complete. After post-processing, the anti-aging additive is obtained.

[0016] Preferably, the ratio of melamine to phenyl isothiocyanate in step B1 is 13.9-14.5g:13.5g.

[0017] Preferably, the ratio of 3-hydroxypropionic acid to the intermediate product of the anti-aging additive in step B2 is 20.0-21.5g:26.1g.

[0018] In the above preparation process, the raw materials melamine and phenyl isothiocyanate in step B1 need to be carefully controlled so that their molar ratio is close to 1:1 and the former is in excess to reduce side reactions; similarly, the raw materials 3-hydroxypropionic acid and the intermediate product of the anti-aging additive in step B2 need to be carefully controlled so that their molar ratio is close to 2:1 and the former is in excess to ensure complete reaction.

[0019] The anti-aging additive prepared by this invention simultaneously introduces a triazine ring and a thiourea group into the molecule. Both possess certain anti-aging capabilities. The sulfur atom in the thiourea has reducing properties, which can decompose the peroxides and hydroperoxides generated during the oxidation of polyurethane into alcohols or ketones, terminating the free radical chain reaction. The two can play a synergistic role in improving the antioxidant capacity of the matrix. In addition, a benzene ring is also introduced into the molecule. The benzene ring can not only improve the mechanical strength of the matrix to a certain extent, but also synergistically enhance the thermal aging resistance of the matrix with the triazine ring. Finally, the anti-aging additive contains two primary hydroxyl groups, which can react with isocyanates to form covalent bonds into the polyurethane network. Compared with traditional small molecule additives, it is not easy to migrate and has a good long-term anti-aging effect.

[0020] This invention also provides a method for preparing a fiberglass aluminum foil composite sound insulation material, comprising the following steps: Place the lower layer on a flat heating plate for preheating, then heat and melt the hot melt adhesive and apply it to the surface of the lower layer (the side without the sound-absorbing groove). Immediately afterward, attach the upper layer to the adhesive-coated surface and slowly roll it from one end to the other. Let it stand at room temperature for 24 hours to allow the moisture to fully cure, thus obtaining the fiberglass aluminum foil composite sound insulation material.

[0021] Preferably, the preheating temperature is 50-60°C.

[0022] Preferably, the heating and melting temperature is 130-140°C.

[0023] The beneficial effects of this invention are: 1. This invention combines aluminum foil composite glass fiber cloth with modified polyurethane foam to form a "mass-spring" structure. The aluminum foil acts as the mass block and the polyurethane foam acts as the elastic layer, generating a resonant damping effect in the low-frequency range, which effectively makes up for the defects of ordinary polyurethane foam in that it has strong penetration of low-frequency sound waves and poor isolation effect. 2. Aluminum foil composite fiberglass cloth has high tensile strength and tear resistance. When laminated onto the foam surface, it can withstand most of the tensile, bending and impact loads, while resisting scratches, effectively preventing the foam surface from shedding and cracking under pressure, and improving its service life. 3. The obtained anti-aging additive has excellent anti-aging properties and is not easily migrated, ensuring that the acoustic performance and structural stability of the material do not easily degrade during long-term use.

[0024] In summary, the sound insulation material obtained by this invention has excellent sound insulation effect, mechanical strength and anti-aging properties, and has important application value in the field of sound insulation material technology. Detailed Implementation

[0025] 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.

[0026] Example 1 Preparation of anti-aging additives: B1. At room temperature, 13.9 g of melamine and 100 mL of anhydrous pyridine were added to a three-necked round-bottom flask (equipped with a condenser). The mixture was then heated to 100 °C in an oil bath and stirred to dissolve the melamine. Subsequently, 0.3 g of dibutyltin dilaurate (catalyst) and 13.5 g of phenyl isothiocyanate were added. The mixture was kept at this temperature for 2 h. After the reaction was completed, most of the pyridine was removed by vacuum distillation. The mixture was washed, purified, and dried to obtain the intermediate product of the anti-aging additive. B2. At room temperature, 20.0 g of 3-hydroxypropionic acid and anhydrous N,N-dimethylformamide were added to a flask and stirred until homogeneous. Then, 42.2 g of N-hydroxysuccinimide and 25.3 g of EDC·HCl were added and stirred until homogeneous. Finally, 26.1 g of the intermediate product of the anti-aging additive was added and the mixture was stirred at room temperature for 12 h. After the reaction was completed, most of the DMF was removed by vacuum distillation, followed by washing, purification, and drying to obtain the anti-aging additive.

[0027] Preparation of the lower layer material: A1. According to the formula, 45 parts of polyether polyol, 8 parts of DMMP (methyl dimethylphosphonate), 2 parts of anti-aging additive, 2 parts of water, 1.5 parts of silicone oil foam stabilizer and 0.5 parts of triethylenediamine are dispersed in a stirring tank (1200 rpm) for 5 minutes to obtain white material; A2. Continue to add 35 parts of isocyanate to the mixing vessel, stir rapidly (1800 rpm) for 10 seconds, pour into the mold (preheated to 45℃, the bottom plate of the mold has an array of hemispherical protrusions with a diameter of 15 mm), close the mold and lock it, keep the mold temperature at 50℃, allow it to foam freely for 3 minutes. During the foaming process, the foam wraps around the conical protrusions. After curing, demolding will form sound-absorbing grooves on the surface of the foam. Then let it stand and mature for 12 hours, and finally heat treat it in an oven (120℃) for 1 hour to obtain the lower layer material.

[0028] A method for preparing a fiberglass-aluminum foil composite sound insulation material includes the following steps: Place the lower layer on a flat heating table and preheat it to 50°C. Then heat the moisture-curing polyurethane hot melt adhesive to 130°C to melt it and apply it to the surface of the lower layer (the side without sound-absorbing grooves). Immediately afterward, attach the upper layer (aluminum foil composite fiberglass cloth, 8μm thick, with a weave density of 20×18) to the adhesive surface and slowly roll it from one end to the other. Let it stand at room temperature for 24 hours to allow the moisture to fully cure, thus obtaining the fiberglass aluminum foil composite sound insulation material.

[0029] Example 2 Preparation of anti-aging additives: B1. At room temperature, 14.5 g of melamine and 100 mL of anhydrous pyridine were added to a three-necked round-bottom flask (equipped with a condenser). The mixture was then heated to 105 °C in an oil bath and stirred to dissolve the melamine. Subsequently, 0.3 g of dibutyltin dilaurate (catalyst) and 13.5 g of phenyl isothiocyanate were added. The mixture was kept at this temperature for 3 h. After the reaction was completed, most of the pyridine was removed by vacuum distillation. The mixture was washed, purified, and dried to obtain the intermediate product of the anti-aging additive. B2. At room temperature, 21.5 g of 3-hydroxypropionic acid and anhydrous N,N-dimethylformamide were added to a flask and stirred until homogeneous. Then, 42.2 g of N-hydroxysuccinimide and 25.3 g of EDC·HCl were added and stirred until homogeneous. Finally, 26.1 g of the intermediate product of the anti-aging additive was added and the mixture was stirred at room temperature for 16 h. After the reaction was completed, most of the DMF was removed by vacuum distillation, followed by washing, purification, and drying to obtain the anti-aging additive.

[0030] Preparation of the lower layer material: A1. According to the formula, 50 parts of polyether polyol, 9 parts of DMMP (methyl dimethylphosphonate), 3 parts of anti-aging additive, 2.5 parts of water, 2.0 parts of silicone oil foam stabilizer and 0.6 parts of triethylenediamine are dispersed in a stirring tank (1500 rpm) for 10 min to obtain white material; A2. Continue to add 39 parts of isocyanate to the mixing vessel, stir rapidly (2000 rpm) for 10 seconds, pour into the mold (preheated to 50°C, the bottom plate of the mold has an array of hemispherical protrusions with a diameter of 15 mm), close the mold and lock it, keep the mold temperature at 55°C, allow it to foam freely for 5 minutes. During the foaming process, the foam will wrap around the conical protrusions. After curing, demolding will form sound-absorbing grooves on the surface of the foam. Then let it stand and mature for 24 hours, and finally heat treat it in an oven (120°C) for 2 hours to obtain the lower layer material.

[0031] A method for preparing a fiberglass-aluminum foil composite sound insulation material includes the following steps: Place the lower layer on a flat heating plate and preheat it to 60°C. Then heat the moisture-curing polyurethane hot melt adhesive to 140°C to melt it and apply it to the surface of the lower layer (the side without sound-absorbing grooves). Immediately afterward, attach the upper layer (aluminum foil composite fiberglass cloth, 8μm thick, with a weave density of 20×18) to the adhesive-coated surface and slowly roll it from one end to the other. Let it stand at room temperature for 24 hours to allow the moisture to fully cure, thus obtaining the fiberglass aluminum foil composite sound insulation material.

[0032] Example 3 The only difference between this embodiment and Embodiment 2 is that, in this embodiment, the lower layer material is prepared through the following steps: A1. According to the formula, 55 parts of polyether polyol, 10 parts of DMMP (dimethylphosphonate), 4 parts of anti-aging additive, 3 parts of water, 2.5 parts of silicone oil foam stabilizer and 0.7 parts of triethylenediamine are dispersed in a stirring tank (1500 rpm) for 10 min to obtain white material; A2. Continue to add 42 parts of isocyanate to the mixing vessel, stir rapidly (2000 rpm) for 10 seconds, pour into the mold (preheated to 50°C, the bottom plate of the mold has an array of hemispherical protrusions with a diameter of 15 mm), close the mold and lock it, keep the mold temperature at 55°C, allow it to foam freely for 5 minutes. During the foaming process, the foam will wrap around the conical protrusions. After curing, demolding will form sound-absorbing grooves on the surface of the foam. Then let it stand and mature for 24 hours, and finally heat treat it in an oven (120°C) for 2 hours to obtain the lower layer material.

[0033] A method for preparing a fiberglass-aluminum foil composite sound insulation material includes the following steps: Place the lower layer on a flat heating plate and preheat it to 60°C. Then heat the moisture-curing polyurethane hot melt adhesive to 140°C to melt it and apply it to the surface of the lower layer (the side without sound-absorbing grooves). Immediately afterward, attach the upper layer (aluminum foil composite fiberglass cloth, 8μm thick, with a weave density of 20×18) to the adhesive-coated surface and slowly roll it from one end to the other. Let it stand at room temperature for 24 hours to allow the moisture to fully cure, thus obtaining the fiberglass aluminum foil composite sound insulation material.

[0034] Comparative Example 1 The difference between this comparative example and Example 3 is that no anti-aging additives are added in this comparative example to obtain the sound insulation material.

[0035] Comparative Example 2 The difference between this comparative example and Comparative Example 1 is that in this comparative example, only the lower layer material is used as the sound insulation material.

[0036] The sound absorption coefficients of Examples 1, 2, and 3 and Comparative Examples 1 and 2 were measured at 500 Hz and 2000 Hz, respectively. The following performance tests were conducted on the lower layer material (polyurethane foam) of Examples 1, 2, and 3 and Comparative Example 1: The compressive strength of the specimens was determined according to GB / T 8813-2020 standard; The retention rate of compressive strength of the sample after aging at 120℃ for 168 hours was determined according to GB / T 9640-2008 standard.

[0037] The measurement results are shown in Table 1: Table 1 As can be seen from the test results in Table 1, the sound insulation material prepared by the embodiment of the present invention has excellent sound insulation performance, and its compressive strength and anti-aging performance are higher than those of the comparative example. Therefore, the present invention has important application value in the field of sound insulation material technology.

[0038] 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. A fiberglass-aluminum foil composite sound insulation material, comprising an upper layer and a lower layer, wherein the upper and lower layers are bonded together by hot melt adhesive, characterized in that, The material of the lower layer comprises the following raw materials in parts by weight: 45-55 parts polyether polyol, 35-42 parts isocyanate, 8-10 parts flame retardant, 2-4 parts anti-aging additive, 2-3 parts water, 1.5-2.5 parts foam stabilizer and 0.5-0.7 parts catalyst.

2. The fiberglass aluminum foil composite sound insulation material according to claim 1, characterized in that, The upper layer material is aluminum foil composite glass fiber cloth.

3. The fiberglass aluminum foil composite sound insulation material according to claim 1, characterized in that, The lower layer material is prepared through the following steps: A1. Disperse polyether polyol, flame retardant, anti-aging additive, water, foam stabilizer and catalyst in a stirred tank to obtain white material; A2. Continue to add isocyanate to the mixing vessel, stir quickly, pour into the mold, close and lock the mold. The mold temperature is 50-55℃. After free foaming and curing, demold, let stand and mature, and finally heat treat in an oven to obtain the lower layer material.

4. The fiberglass aluminum foil composite sound insulation material according to claim 1, characterized in that, The anti-aging additive is prepared by the following steps: B1. Melamine and anhydrous pyridine are added to a flask, heated to 100-105℃, and stirred to dissolve the melamine. Then, dibutyltin dilaurate and phenyl isothiocyanate are added, and the reaction is maintained at the temperature for 2-3 hours. Once the reaction is complete, an intermediate product of the anti-aging additive is obtained. B2. Add 3-hydroxypropionic acid and anhydrous N,N-dimethylformamide to a flask, stir until homogeneous, then add N-hydroxysuccinimide and EDC·HCl, stir until homogeneous, then add the intermediate product of the anti-aging additive, stir at room temperature for 12-16 hours until the reaction is complete, and the anti-aging additive is obtained.

5. The fiberglass aluminum foil composite sound insulation material according to claim 3, characterized in that, The mold base plate is provided with an array of hemispherical protrusions.

6. The fiberglass aluminum foil composite sound insulation material according to claim 4, characterized in that, In step B1, the ratio of melamine to phenyl isothiocyanate is 13.9-14.5g:13.5g.

7. The fiberglass aluminum foil composite sound insulation material according to claim 4, characterized in that, In step B2, the ratio of 3-hydroxypropionic acid to the intermediate product of the anti-aging additive is 20.0-21.5g:26.1g.

8. A method for preparing a fiberglass-aluminum foil composite sound insulation material, used in the fiberglass-aluminum foil composite sound insulation material according to any one of claims 1-7, characterized in that, Includes the following steps: The lower layer is placed on a flat heating table for preheating. Then, hot melt adhesive is heated and melted, and applied to the surface of the lower layer. The upper layer is then immediately bonded to the adhesive surface, rolled and laminated, and left to stand at room temperature to allow the moisture to fully cure, thus obtaining the fiberglass aluminum foil composite sound insulation material.

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