A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles and its molding method

Abstract

The present invention relates to a polyurethane sound-absorbing tile integrating multiple sound-absorbing principles and a forming method thereof, belonging to the technical field of sound-absorbing structures. The sound-absorbing tile sequentially comprises a first-layer polyurethane elastomer, a second-layer microporous polyurethane elastomer and a third-layer polyurethane elastomer from bottom to top; the first-layer polyurethane elastomer is a polyurethane elastomer with a density of 1100-1200 kg / m<supgt;3< / supgt>, an elastic modulus of 7×10<supgt;6< / supgt>-10×10<supgt;6< / supgt> Pa and a loss factor of 0.8-1.0, and a thickness of 4-6 mm; the second-layer microporous polyurethane elastomer is a microporous polyurethane elastomer with a density of 880-950 kg / m<supgt;3 and a closed-cell rate of 90%-92%, and a thickness of 40-42 mm; the third-layer polyurethane elastomer is a polyurethane elastomer with a density of 1000-1100 kg / m<supgt;3 and a characteristic acoustic impedance of 1.5×10<supgt;6-1.8×10<supgt;6 kg·m<supgt;‑2·s<supgt;‑1, and a thickness of 5-7 mm. The design makes full use of four sound-absorbing principles, namely impedance matching, damping dissipation, scattering and cavity resonance, to effectively improve the sound-absorbing effect of the sound-absorbing tile.

Description

Technical Field

[0001] The present invention relates to a polyurethane sound-absorbing tile integrating multiple sound-absorbing principles and a forming method thereof, belonging to the technical field of sound-absorbing structures. Background Art

[0002] As a highly deterrent naval ship type, stealth is a major feature of a submarine and a prerequisite for exerting its combat effectiveness. A sound-absorbing tile is a submarine stealth equipment with strong sound-absorbing ability, mainly used to cover the underwater submarine hull, suppress the hull vibration and absorb the enemy's active sonar, reduce the sound reflection intensity of the submarine, and achieve the purpose of reducing the detection distance.

[0003] Domestic and foreign sound-absorbing tiles mostly adopt styrene-butadiene rubber and polysulfide rubber materials, and the United Kingdom uses polyurethane spraying to prepare polyurethane sound-absorbing tiles. Among them, the rubber material sound-absorbing tile has the characteristics of good high-frequency sound absorption, poor low-frequency sound absorption, and the sound velocity and attenuation constant are related to temperature and frequency, and it is greatly affected by temperature. As the water pressure increases, the sound absorption coefficient decreases. The polyurethane material sound-absorbing tile has good underwater sound absorption and a wide sound absorption frequency band. As the water pressure increases, the change degree of the sound absorption coefficient is significantly smaller than that of rubber. However, the sound-absorbing principle of the existing sound-absorbing tiles is mostly single, that is, the damping dissipation principle. When deforming under the action of sound waves, part of the sound energy is converted into heat energy and dissipated by using the internal friction and elastic relaxation processes of the material. The sound-absorbing effect needs to be further improved. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a polyurethane sound-absorbing tile integrating multiple sound-absorbing principles and a forming method thereof, which are designed by fully utilizing four sound-absorbing principles of impedance matching, damping dissipation, scattering, and cavity resonance, and effectively improve the sound absorption coefficient of the sound-absorbing tile.

[0005] To achieve the above purpose, the technical solution of the present invention is as follows:

[0006] A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles, the sound-absorbing tile sequentially includes a first-layer polyurethane elastomer, a second-layer microporous polyurethane elastomer, and a third-layer polyurethane elastomer from bottom to top; wherein, the first-layer polyurethane elastomer is a polyurethane elastomer with a density of 1100-1200 kg / m 3 and an elastic modulus of 7×10 6 -10×10 6 Pa and a loss factor of 0.8-1.0, and the thickness is 4-6 mm; the second-layer microporous polyurethane elastomer is a polyurethane elastomer with a density of 880-950 kg / m 3, a microporous polyurethane elastomer with a closed cell rate of 90% to 92% and a thickness of 40 to 42 mm; the third layer of polyurethane elastomer is obtained by reacting and curing the third A component and the third B component to form a density of 1000 to 1100 kg / m 3 , with a characteristic acoustic impedance of 1.5×10 6 ~1.8×10 6 kg·m -2 ·s -1 of polyurethane elastomer and a thickness of 5 to 7 mm.

[0007] Preferably, the lower surface of the first layer of polyurethane elastomer is in contact with the component to be protected, and the lower surface of the first layer of polyurethane elastomer is a non-smooth surface, such as a sawtooth structure or a corrugated structure; circular cavities in a wedge array are distributed at intervals in the second layer of microporous polyurethane elastomer; when used as a sound absorption structure for large-sized components to be protected (such as submarines, etc.), the sound absorption tiles are integrally assembled by splicing.

[0008] Preferably, the first A component is prepared by uniformly mixing polyether polyol, chain extender, catalyst, defoaming agent, and filler; the polyether polyol is polytetrahydrofuran ether glycol with a molecular weight of 1000 (PTMEG1000); the chain extender is dimethylthiotoluenediamine (DMTDA); the catalyst is dibutyltin dilaurate (T12); the defoaming agent is the defoaming agent with the brand name F-2293 from Guangdong Tianfeng Defoaming Agent Co., Ltd.; the filler is mica powder;

[0009] Based on the total mass of the raw materials for preparing the first A component being 100 parts, the components and their mass parts are as follows:

[0010]

[0011]

[0012] The first B component is a prepolymer with an -NCO value between 13 and 18 formed by reacting diisocyanate and polyether polyol under nitrogen protection at 80 to 100 °C for 4 h to 6 h;

[0013] Based on the total mass of the raw materials for preparing the first B component being 100 parts, the components and their mass parts are as follows:

[0014] Diisocyanate 50 - 60 parts;

[0015] Polyether polyol 40 - 50 parts;

[0016] The molar ratio of the active - H contained in the first A component (the active - H in polyol - OH) to the - NCO groups contained in the first B component (the - NCO remaining after the reaction of diisocyanate and polyether polyol, i.e., the - NCO in the prepolymer) is 1.00:0.98 to 1.00:1.02.

[0017] Preferably, the particle size of the mica powder is 150 - 200 μm.

[0018] Preferably, based on the total mass of 100 parts of the raw materials for preparing the first A component, the components of the raw materials and their mass parts are as follows:

[0019]

[0020] Preferably, the diisocyanate in the first B component is diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI); the polyether polyol is polypropylene glycol with a molecular weight of 1000 (PPG1000); based on the total mass of 100 parts of the raw materials for preparing the first B component, the components of the raw materials and their mass parts are as follows:

[0021] MDI 38 - 45 parts;

[0022] TDI 8 - 15 parts;

[0023] PPG1000 45 - 50 parts.

[0024] Preferably, the molar ratio of the active - H contained in the first A component to the - NCO groups contained in the first B component is 1.00:0.99 to 1.01.

[0025] Preferably, the second A component is prepared by uniformly mixing polyether polyol, chain extender, foaming agent, foam stabilizer, catalyst, and filler; the polyether polyol is polytetrahydrofuran ether glycol with a molecular weight of 1000 (PTMEG1000); the chain extender is dimethylthiotoluenediamine (DMTDA); the foaming agent is H 2 O; the foam stabilizer is the foam stabilizer with the trade name AK7703 from Jiangsu MSD Chemical Co., Ltd.; the catalyst is bis(dimethylaminoethyl) ether (BDMAE) and dibutyltin dilaurate (T12); the filler is graphite powder;

[0026] Based on the total mass of 100 parts of the raw materials for preparing the second A component, the components of the raw materials and their mass parts are as follows:

[0027]

[0028] The second B component is a prepolymer with an -NCO value between 13 and 18, formed by stirring and reacting diisocyanate and polyether polyol at 80 - 100 °C for 4 - 6 h under a nitrogen protection atmosphere;

[0029] Based on the total mass of 100 parts of the raw materials for preparing the second B component, the components and their mass parts are as follows:

[0030] Diisocyanate 50 - 60 parts;

[0031] Polyether polyol 40 - 50 parts;

[0032] The active -H contained in the second A component (the sum of the active -H in polyol -OH and the active -H in H 2 O) and the -NCO groups contained in the second B component (the -NCO remaining after the reaction of diisocyanate and polytetrahydrofuran ether polyol, that is, the -NCO in the prepolymer) have a molar ratio of 1.00:0.98 - 1.00:1.02.

[0033] Preferably, the particle size of the graphite powder is 30 - 50 μm.

[0034] Preferably, based on the total mass of 100 parts of the raw materials for preparing the second A component, the components and their mass parts are as follows:

[0035]

[0036] Preferably, the diisocyanate in the second B component is diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI); the polyether polyol is PTMEG1000; based on the total mass of 100 parts of the raw materials for preparing the second B component, the components and their mass parts are as follows:

[0037] MDI 38 - 45 parts;

[0038] TDI 8 - 15 parts;

[0039] PTMEG1000 45 - 50 parts.

[0040] Preferably, the molar ratio of the active -H contained in the second A component to the -NCO groups contained in the second B component is 1.00:0.99 - 1.01.

[0041] Preferably, the third A component is prepared by uniformly mixing polyether polyol, chain extender, catalyst, and defoamer; the polyether polyol is polytetrahydrofuran ether diol with molecular weights of 1000 and 2000 (PTMEG1000 and PTMEG2000); the chain extender is dimethylthiotoluenediamine (DMTDA); the catalyst is dibutyltin dilaurate (T12); the defoamer is the defoamer with the brand number F-2293 from Guangdong Tianfeng Defoamer Co., Ltd.;

[0042] Based on the total mass of the raw materials for preparing the third A component being 100 parts, the components of each raw material and their mass parts are as follows:

[0043]

[0044] The third B component is a prepolymer with an -NCO value between 13 and 18 formed by reacting diisocyanate and polyether polyol under nitrogen protection at 80 - 100 °C for 4 - 6 hours;

[0045] Based on the total mass of the raw materials for preparing the third B component being 100 parts, the components of each raw material and their mass parts are as follows:

[0046] Diisocyanate 50 - 60 parts;

[0047] Polyether polyol 40 - 50 parts;

[0048] The molar ratio of the active -H (the active -H in polyol -OH) contained in the third A component to the -NCO group (the -NCO remaining after the reaction of diisocyanate and polyether polyol, that is, the -NCO in the prepolymer) contained in the third B component is 1.00:0.98 - 1.02.

[0049] Preferably, based on the total mass of the raw materials for preparing the third A component being 100 parts, the components of each raw material and their mass parts are as follows:

[0050]

[0051] Preferably, the diisocyanate in the third B component is diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI); the polyether polyol is PTMEG1000; based on the total mass of the raw materials for preparing the third B component being 100 parts, the components of each raw material and their mass parts are as follows:

[0052] MDI 38 - 45 parts;

[0053] TDI 8 - 15 parts;

[0054] PTMEG1000 45 - 50 parts;

[0055] Preferably, the molar ratio of the active - H contained in the third A component to the - NCO group contained in the third B component is 1.00:0.99 - 1.01.

[0056] A molding method of the polyurethane sound - absorbing tile integrated with multiple sound - absorption principles according to the present invention, the method steps include:

[0057] (1) Preheat the first A component, the second A component, and the third A component to 32 ± 2 °C respectively; preheat the first B component, the second B component, and the third B component to 40 ± 2 °C respectively; preheat the mold to 65 ± 5 °C;

[0058] (2) First, pour the first A component and the first B component into the preheated mold for curing. After 8 - 15 minutes, the material cures and forms the first - layer polyurethane elastomer in the mold; then pour the second A component and the second B component onto the first - layer polyurethane elastomer. After 8 - 15 minutes, the material cures and forms the second - layer microporous polyurethane elastomer in the mold; finally, pour the third A component and the third B component onto the second - layer microporous polyurethane elastomer. After 8 - 15 minutes, the material cures and forms the third - layer polyurethane elastomer in the mold, and demold to obtain a polyurethane sound - absorbing tile integrated with multiple sound - absorption principles.

[0059] Preferably, cylinders are provided at the position of the second - layer microporous polyurethane elastomer in the mold, and are distributed in a wedge - shaped array.

[0060] Beneficial effects

[0061] (1) The present invention provides a polyurethane sound - absorbing tile integrated with multiple sound - absorption principles, which fully utilizes four sound - absorption principles of impedance matching, damping dissipation, scattering, and cavity resonance for design, effectively improving the sound - absorption effect of the sound - absorbing tile. Specifically: The characteristic acoustic impedance of the third - layer polyurethane elastomer of the sound - absorbing tile is close to that of seawater, with strong sound - transmission performance. When sound waves pass through this layer, most of them will pass through, part of them will be absorbed, and the sound reflection is very small. The second - layer microporous polyurethane elastomer has little influence on the acoustic impedance of the material, but the added micropores can increase the sound - energy attenuation; when sound waves propagate in this layer of material, it will cause the air movement in the micropores, and the sound waves will be reflected and absorbed multiple times on the pore walls. Due to the viscosity of air and the heat - conduction effect between the pore walls and air, the sound - energy is attenuated; at the same time, due to the cavity - resonance effect of this layer, the sound waves are reflected and absorbed multiple times in this layer, and most of the sound - energy will be dissipated. The first - layer polyurethane elastomer increases the damping performance of the material, has a good sound - absorption effect on low - frequency sound waves, and can effectively suppress the structural vibration of the submarine and reduce the noise. The combined action of the three - layer materials can effectively improve the sound - absorption coefficient of the sound - absorbing tile, especially solving the problem of sound - absorption of low - frequency sound waves that many sound - absorbing materials are difficult to solve.

[0062] (3) The micropores of the second-layer microporous polyurethane elastomer can cause multiple reflections and absorptions of sound waves, playing a key role in the dissipation of sound energy. However, if the number of micropores is too large, the strength of the material will be reduced. Therefore, the density of the microporous polyurethane elastomer should be controlled within a suitable range. As the dosage of graphite powder increases, the number of interfaces increases, and the damping dissipation increases, which can improve the sound attenuation performance of the sound-absorbing tile. However, if the addition amount is too large, it will affect the strength of the material. Therefore, the addition amount of graphite powder should be controlled within a suitable range.

[0063] (4) Introducing PPG with side methyl groups on the molecular chain into the first-layer polyurethane elastomer greatly increases the damping performance of the material. If the particle size of mica powder in the first-layer material is too small, its dispersibility in the matrix is good, but the interfacial compatibility is also good, so the damping dissipation is small; if the particle size is too large, its dispersibility in the matrix is poor, resulting in a decrease in strength. Therefore, the particle size should be controlled within a suitable range. Description of the Drawings

[0064] Figure 1 Schematic diagram of the structure of a polyurethane sound-absorbing tile integrating multiple sound-absorbing principles according to the present invention.

[0065] Figure 2 Splicing method diagram of the sound-absorbing tile according to the present invention.

[0066] Among them, 1 - the first-layer polyurethane elastomer, 2 - the second-layer microporous polyurethane elastomer, 3 - the third-layer polyurethane elastomer. Detailed Description of the Invention

[0067] The present invention will be further described in detail below with reference to specific embodiments.

[0068] In the following examples or comparative examples, the defoamer is the defoamer with the brand number F-2293 produced by Guangdong Tianfeng Defoamer Co., Ltd.; the particle size of the graphite powder is 30 - 50 μm; the particle size of the mica powder is 150 - 200 μm.

[0069] As Figure 1 described, a polyurethane sound-absorbing tile integrating multiple sound-absorbing principles, the sound-absorbing tile sequentially includes a first-layer polyurethane elastomer 1, a second-layer microporous polyurethane elastomer 2, and a third-layer polyurethane elastomer 3 from bottom to top; among them, the first-layer polyurethane elastomer 1 is a polyurethane elastomer with a density of 1100 - 1200 kg / m 3 and an elastic modulus of 7×10 6 -10×10 6 Pa and a loss factor of 0.8 - 1.0, and the thickness is 4 - 6 mm; the second-layer microporous polyurethane elastomer 2 is a polyurethane elastomer with a density of 880 - 950 kg / m 3, a microcellular polyurethane elastomer with a closed cell rate of 90% - 92% and a thickness of 40 - 42 mm; the third layer of polyurethane elastomer 3 is obtained by reacting and curing the third A component and the third B component to form a density of 1000 - 1100 kg / m 3 , with a characteristic acoustic impedance of 1.5×10 6 ~1.8×10 6 kg·m -2 ·s -1 of polyurethane elastomer and a thickness of 5 - 7 mm.

[0070] The lower surface of the first layer of polyurethane elastomer is in contact with the component to be protected, and the lower surface of the first layer of polyurethane elastomer is a non-smooth surface, such as a sawtooth structure or a corrugated structure; circular cavities in a wedge-shaped array are distributed at intervals in the second layer of microcellular polyurethane elastomer; when used as a sound-absorbing structure for large-sized components to be protected (such as submarines, etc.), the sound-absorbing tiles are integrally assembled by splicing, as Figure 2 shown.

[0071] Cylinders distributed in a wedge-shaped array are provided at the position of the second layer of microcellular polyurethane elastomer in the molding die.

[0072] Example 1

[0073] (1) Mix 90 parts of PTMEG1000, 7 parts of DMTDA, 0.01 part of T12, 0.99 part of F-2293, and 2 parts of mica powder evenly to obtain the first A component; mix 50.2 parts of PTMEG1000, 14 parts of DMTDA, 0.09 part of H 2 O, 0.10 part of BDMAE (bis(dimethylaminoethyl) ether), 0.6 part of AK7703, 0.01 part of T-12 (dibutyltin dilaurate), and 35 parts of graphite powder evenly to obtain the second A component; mix 68 parts of PTMEG1000, 26 parts of PTMEG2000, 5 parts of DMTDA, 0.015 part of T12, and 0.985 part of F-2293 evenly to obtain the third A component.

[0074] (2) After mixing 10 parts of TDI, 40 parts of MDI, and 50 parts of PPG1000, stir and react at 80°C for 6 h in a nitrogen protection atmosphere to obtain the first B component; after mixing 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, stir and react at 80°C for 6 h in a nitrogen protection atmosphere to obtain the second B component; after mixing 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, stir and react at 100°C for 4 h in a nitrogen protection atmosphere to obtain the third B component.

[0075] (3) Preheat the first A component, the second A component, and the third A component to 32 ± 2 °C respectively, preheat the first B component, the second B component, and the third B component to 40 ± 2 °C respectively, and preheat the mold to 65 ± 5 °C for standby.

[0076] (4) First, mix the first A component and the first B component evenly according to the molar ratio of active -H in the first A component to -NCO groups in the first B component of 1:1 through a two - component polyurethane casting machine, and then pour them into the preheated mold for curing, with a thickness of 5 mm. After 10 minutes, the material cures and forms in the mold. Then, mix the second A component and the second B component evenly according to the molar ratio of active -H in the second A component to -NCO groups in the second B component of 1:1 through a two - component polyurethane casting machine, and pour them onto the first layer, with a thickness of 40 mm. After 15 minutes, the material cures and forms in the mold. Finally, mix the third A component and the third B component evenly according to the molar ratio of active -H in the third A component to -NCO groups in the third B component of 1:1 through a two - component polyurethane casting machine, and pour them onto the second layer, with a thickness of 5 mm. After 10 minutes, the material cures and forms in the mold, obtaining a polyurethane sound - absorbing tile integrated with multiple sound - absorption principles.

[0077] Example 2

[0078] (1) Mix 88 parts of PTMEG1000, 7 parts of DMTDA, 0.01 part of T12, 0.99 part of F - 2293, and 4 parts of mica powder evenly to obtain the first A component; mix 48.2 parts of PTMEG1000, 16 parts of DMTDA, 0.09 part of 2 H₂O, 0.10 part of BDMAE (bis(dimethylaminoethyl) ether), 0.6 part of AK7703, 0.01 part of T - 12 (dibutyltin dilaurate), and 35 parts of graphite powder evenly to obtain the second A component; mix 70 parts of PTMEG1000, 24 parts of PTMEG2000, 5 parts of DMTDA, 0.015 part of T12, and 0.985 part of F - 2293 evenly to obtain the third A component.

[0079] (2) Mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PPG1000, and then stir - react at 100 °C for 4 h in a nitrogen - protected atmosphere to obtain the first B component; mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, and then stir - react at 900 °C for 5 h in a nitrogen - protected atmosphere to obtain the second B component; mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, and then stir - react at 90 °C for 5 h in a nitrogen - protected atmosphere to obtain the third B component.

[0080] (3) Preheat the first A component, the second A component, and the third A component to 32 ± 2 °C respectively, preheat the first B component, the second B component, and the third B component to 40 ± 2 °C respectively, and preheat the mold to 65 ± 5 °C for standby.

[0081] (4) First, mix the first A component and the first B component evenly according to the molar ratio of active -H in the first A component to -NCO groups in the first B component of 1:1 through a two - component polyurethane casting machine, then pour them into the preheated mold for curing, with a thickness of 5 mm. After 15 minutes, the material cures and forms in the mold; then mix the second A component and the second B component evenly according to the molar ratio of active -H in the second A component to -NCO groups in the second B component of 1:1 through a two - component polyurethane casting machine, and pour them onto the first layer, with a thickness of 40 mm. After 15 minutes, the material cures and forms in the mold; finally, mix the third A component and the third B component evenly according to the molar ratio of active -H in the third A component to -NCO groups in the third B component of 1:1 through a two - component polyurethane casting machine, and pour them onto the second layer, with a thickness of 5 mm. After 8 minutes, the material cures and forms in the mold, obtaining a polyurethane sound - absorbing tile integrated with multiple sound - absorption principles.

[0082] Comparative Example 1

[0083] (1) Mix 50.2 parts of PTMEG1000, 14 parts of DMTDA, 0.09 part of H 2 O, 0.10 part of BDMAE (bis(dimethylaminoethyl) ether), 0.6 part of AK7703, 0.01 part of T - 12 (dibutyltin dilaurate) and 35 parts of graphite powder evenly to obtain the A component;

[0084] (2) After mixing 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, stir and react at 100 °C for 5 h under a nitrogen - protection atmosphere to obtain the B component.

[0085] (3) Preheat the A component to 32 ± 2 °C, preheat the B component to 40 ± 2 °C, and preheat the mold to 65 ± 5 °C for standby.

[0086] (4) Mix the A component and the B component evenly according to the molar ratio of active -H in the A component to -NCO groups in the B component of 1:1 through a two - component polyurethane casting machine, and then pour them into the mold at one time, with a thickness of 50 mm. After curing for 15 minutes, obtain a polyurethane sound - absorbing tile.

[0087] Comparative Example 2

[0088] (1) Mix 50.2 parts of PTMEG1000, 14 parts of DMTDA, 0.09 part of H 2Mix 0 part of O, 0.10 part of BDMAE (bis(dimethylaminoethyl) ether), 0.6 part of AK7703, 0.01 part of T-12 (dibutyltin dilaurate), and 35 parts of graphite powder evenly to obtain the first A component; mix 68 parts of PTMEG1000, 26 parts of PTMEG2000, 5 parts of DMTDA, 0.015 part of T12, and 0.985 part of F-2293 evenly to obtain the second A component.

[0089] (2) Mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, and then stir and react at 80 °C for 6 h in a nitrogen protection atmosphere to obtain the B component.

[0090] (3) Preheat the first A component and the second A component to 32 ± 2 °C respectively, preheat the B component to 40 ± 2 °C, and preheat the mold to 65 ± 5 °C for standby.

[0091] (4) Mix the first A component and the B component evenly by a two-component polyurethane casting machine according to the molar ratio of active -H in the first A component to -NCO groups in the B component of 1:1, and then pour them into the mold with a thickness of 45 mm. After curing for 8 - 15 minutes, mix the second A component and the B component evenly by a two-component polyurethane casting machine according to the molar ratio of active -H in the second A component to -NCO groups in the B component of 1:1, and then pour them onto the first layer with a thickness of 5 mm to obtain a polyurethane sound-absorbing tile.

[0092] Comparative Example 3

[0093] (1) Mix 90 parts of PTMEG1000, 7 parts of DMTDA, 0.01 part of T12, 0.99 part of F-2293, and 2 parts of mica powder evenly to obtain the first A component; mix 50.2 parts of PTMEG1000, 14 parts of DMTDA, 0.09 part of H 2 Mix 0 part of O, 0.10 part of BDMAE (bis(dimethylaminoethyl) ether), 0.6 part of AK7703, 0.01 part of T-12 (dibutyltin dilaurate), and 35 parts of graphite powder evenly to obtain the second A component; mix 68 parts of PTMEG1000, 26 parts of PTMEG2000, 5 parts of DMTDA, 0.015 part of T12, and 0.985 part of F-2293 evenly to obtain the third A component.

[0094] (2) Mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PPG1000, and stir and react at 100 °C for 4 h in a nitrogen-protected atmosphere to obtain the first B component; mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, and stir and react at 80 °C for 6 h in a nitrogen-protected atmosphere to obtain the second B component; mix 10 parts of TDI, 40 parts of MDI, and 50 parts of PTMEG1000, and stir and react at 100 °C for 4 h in a nitrogen-protected atmosphere to obtain the third B component.

[0095] (3) Preheat the first A component, the second A component, and the third A component to 32 ± 2 °C respectively, and preheat the first B component, the second B component, and the third B component to 40 ± 2 °C respectively. Preheat the mold to 65 ± 5 °C for standby.

[0096] (4) First, mix the first A component and the first B component evenly according to the molar ratio of active -H in the first A component to -NCO groups in the first B component of 1:1 through a two-component polyurethane casting machine, and then pour them into the preheated mold for curing, with a thickness of 7 mm. After 15 minutes, the material cures and forms in the mold; then mix the second A component and the second B component evenly according to the molar ratio of active -H in the second A component to -NCO groups in the second B component of 1:1 through a two-component polyurethane casting machine, and pour them onto the first layer, with a thickness of 35 mm. After 15 minutes, the material cures and forms in the mold; finally, mix the third A component and the third B component evenly according to the molar ratio of active -H in the third A component to -NCO groups in the third B component of 1:1 through a two-component polyurethane casting machine, and pour them onto the second layer, with a thickness of 8 mm. After 10 minutes, the material cures and forms in the mold to obtain a polyurethane sound-absorbing tile.

[0097] The sound absorption performance test refers to the standard GB / T 14369-2011 "Measurement Methods for Insertion Loss and Echo Reduction of Acoustic Underwater Material Samples"; the tensile strength and elongation at break tests refer to the standard GB / T 528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber"; the tear strength test refers to the standard GB / T 529-2008 "Determination of Tear Strength of Vulcanized Rubber or Thermoplastic Rubber (Trouser, Right-Angle and Crescent Specimens)"; the performance test results of the sound-absorbing tiles in the examples and comparative examples are shown in Table 1.

[0098] Table 1

[0099]

[0100]

[0101] In summary, the invention includes but is not limited to the above embodiments. Any equivalent substitution or partial improvement made under the spirit and principle of the present invention shall be regarded as within the protection scope of the present invention.

Claims

1. A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles, Characterized in that: The sound-absorbing tile sequentially includes a first layer of polyurethane elastomer, a second layer of microcellular polyurethane elastomer, and a third layer of polyurethane elastomer from bottom to top; wherein, the first layer of polyurethane elastomer is obtained by reacting and curing a first A component and a first B component, and has a density of 1100 - 1200 kg / m 3 , an elastic modulus of 7×10 6 - 10×10 6 Pa, a loss factor of 0.8 - 1.0, and a thickness of 4 - 6 mm; the second layer of microcellular polyurethane elastomer is obtained by reacting and curing a second A component and a second B component, and has a density of 880 - 950 kg / m 3 , a closed-cell rate of 90% - 92%, and a thickness of 40 - 42 mm; the third layer of polyurethane elastomer is obtained by reacting and curing a third A component and a third B component, and has a density of 1000 - 1100 kg / m 3 , a characteristic acoustic impedance of 1.5×10 6 - 1.8×10 6 kg·m -2 ·s -1 , and a thickness of 5 - 7 mm; The lower surface of the first layer of polyurethane elastomer contacts the component to be protected, and the lower surface of the first layer of polyurethane elastomer is a non-smooth surface; circular cavities in a wedge array are distributed at intervals in the second layer of microporous polyurethane elastomer; when used as a sound-absorbing structure for large-sized components to be protected, the sound-absorbing tiles are integrally assembled by splicing.

2. A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles according to claim 1, Characterized in that: The non-smooth surface is a sawtooth structure or a corrugated structure; the large-sized component to be protected is a submarine.

3. A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles according to claim 1, Characterized in that: The first A component is prepared by uniformly mixing polyether polyol, chain extender, catalyst, defoaming agent, and filler; the polyether polyol is PTMEG1000; the chain extender is DMTDA; the catalyst is T12; the defoaming agent is the defoaming agent with the brand F-2293 produced by Guangdong Tianfeng Defoaming Agent Co., Ltd.; the filler is mica powder; Based on the total mass of 100 parts of the raw materials for preparing the first A component, the components and their mass parts are as follows: PTMEG1000 87 - 92 parts; The first B component is a prepolymer with an -NCO value between 13 and 18 formed by stirring and reacting diisocyanate and polyether polyol at 80 - 100 °C for 4 h - 6 h in a nitrogen protection atmosphere; Based on the total mass of 100 parts of the raw materials for preparing the first B component, the components and their mass parts are as follows: Diisocyanate 50 - 60 parts; Polyether polyol 40 - 50 parts; The molar ratio of the active -H contained in the first A component to the -NCO group contained in the first B component is 1.00:0.98 - 1.00:1.

02.

4. A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles according to claim 3, Characterized in that: The particle size of the mica powder is 150 - 200 μm; Based on the total mass of 100 parts of the raw materials for preparing the first A component, the components and their mass parts are as follows: The diisocyanate in the first B component is MDI and TDI; the polyether polyol is PPG1000; based on the total mass of 100 parts of the raw materials for preparing the first B component, the components and their mass parts are as follows: MDI 38 - 45 parts; TDI 8 - 15 parts; PPG1000 45 - 50 parts; The molar ratio of the active -H contained in the first A component to the -NCO group contained in the first B component is 1.00:0.99 - 1.

01.

5. A polyurethane sound-absorbing tile integrating multiple sound-absorbing principles according to claim 1, Characterized in that: The second A component is prepared by uniformly mixing a polyether polyol, a chain extender, a foaming agent, a foam stabilizer, a catalyst, and a filler; the polyether polyol is PTMEG1000; the chain extender is DMTDA; the foaming agent is H 2 O; the foam stabilizer is a foam stabilizer with the brand name AK7703 from Jiangsu MSD Chemical Co., Ltd.; the catalyst is BDMAE and T12; the filler is graphite powder; Based on the total mass of 100 parts of the raw materials for preparing the second A component, the components and their mass parts are as follows: The second B component is a prepolymer with an -NCO value between 13 and 18 formed by stirring and reacting diisocyanate and polyether polyol at 80 - 100 °C for 4 h - 6 h in a nitrogen protection atmosphere; Based on the total mass of the raw materials for preparing the second B component being 100 parts, the respective raw material components and their mass parts are as follows: Diisocyanate 50 - 60 parts; Polyether polyol 40 - 50 parts; The molar ratio of the active - H contained in the second A component to the - NCO groups contained in the second B component is 1.00:0.98 - 1.00:1.

02.

6. A polyurethane sound - absorbing tile integrating multiple sound - absorption principles as described in claim 5, characterized in that: The particle size of the graphite powder is 30 - 50 μm; Based on the total mass of the raw materials for preparing the second A component being 100 parts, the respective raw material components and their mass parts are as follows: The diisocyanate in the second B component is MDI and TDI; the polyether polyol is PTMEG1000; based on the total mass of the raw materials for preparing the second B component being 100 parts, the respective raw material components and their mass parts are as follows: MDI 38 - 45 parts; TDI 8 - 15 parts; PTMEG1000 45 - 50 parts; The molar ratio of the active - H contained in the second A component to the - NCO groups contained in the second B component is 1.00:0.99 - 1.

01.

7. A polyurethane sound - absorbing tile integrating multiple sound - absorption principles as described in claim 1, characterized in that: The third A component is prepared by uniformly mixing polyether polyol, chain extender, catalyst, and defoamer; the polyether polyols are PTMEG1000 and PTMEG2000; the chain extender is DMTDA; the catalyst is T12; the defoamer is the defoamer with the brand number F - 2293 from Guangdong Tianfeng Defoamer Co., Ltd.; Based on the total mass of the raw materials for preparing the third A component being 100 parts, the respective raw material components and their mass parts are as follows: The third B component is a prepolymer with an - NCO value between 13 - 18 formed by reacting diisocyanate and polyether polyol under nitrogen protection at 80 - 100 °C for 4 - 6 h; Based on the total mass of the raw materials for preparing the third B component being 100 parts, the respective raw material components and their mass parts are as follows: Diisocyanate 50 - 60 parts; Polyether polyol 40 - 50 parts; The molar ratio of the active - H contained in the third A component to the - NCO groups contained in the third B component is 1.00:0.98 - 1.

02.

8. A polyurethane sound - absorbing tile integrating multiple sound - absorption principles as described in claim 7, characterized in that: Based on the total mass of the raw materials for preparing the third A component being 100 parts, the respective raw material components and their mass parts are as follows: The diisocyanate in the third B component is MDI and TDI; the polyether polyol is PTMEG1000; based on the total mass of the raw materials for preparing the third B component being 100 parts, the respective raw material components and their mass parts are as follows: MDI 38 - 45 parts; TDI 8 - 15 parts; PTMEG1000 45 - 50 parts; The molar ratio of the active - H contained in the third A component to the - NCO groups contained in the third B component is 1.00:0.99 - 1.

01.

9. A molding method of a polyurethane sound-absorbing tile integrated with multiple sound-absorbing principles as described in any one of claims 1 to 8, characterized in that: The method steps include: (1) Preheat the first A component, the second A component, and the third A component to 32 ± 2 °C respectively; preheat the first B component, the second B component, and the third B component to 40 ± 2 °C respectively; preheat the mold to 65 ± 5 °C; (2) First, pour the first A component and the first B component into the preheated mold for curing. After 8 - 15 minutes, the material cures and forms the first layer of polyurethane elastomer in the mold; then pour the second A component and the second B component onto the first layer of polyurethane elastomer. After 8 - 15 minutes, the material cures and forms the second layer of microporous polyurethane elastomer in the mold; finally, pour the third A component and the third B component onto the second layer of microporous polyurethane elastomer. After 8 - 15 minutes, the material cures and forms the third layer of polyurethane elastomer in the mold, and demold to obtain a polyurethane sound-absorbing tile integrated with multiple sound-absorbing principles.

10. A molding method of a polyurethane sound-absorbing tile integrated with multiple sound-absorbing principles as described in claim 9, characterized in that: Cylinders distributed in a wedge-shaped array are provided at the position of the second layer of microporous polyurethane elastomer in the mold.

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