Silencing and noise reduction composite material and preparation method thereof

Abstract

The invention discloses a sound attenuation and noise reduction composite material and a preparation method thereof, and is characterized in that the sound attenuation and noise reduction composite material is formed by compounding a beater sheet, a metal substrate and a rubber layer; the beater sheet, the metal substrate and the rubber layer are compounded according to the sequence of the rubber layer, the beater sheet, the metal substrate, the beater sheet and the rubber layer; the composite material has a remarkable effect in the aspects of sound attenuation and noise reduction, the sound absorption coefficient can reach 0.6-0.9 in the middle-high frequency band, the noise reduction amount can reach 15-30 dB A, meanwhile, the composite material has good mechanical performance, the tensile strength is 10-20 MPa, the bending strength is 20-30 MPa, the impact strength is 5-10 kJ / m, and the requirements of various practical application scenes can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and particularly to a composite material of a wet laid mat, a metal substrate and a rubber layer for noise reduction and its preparation method. Background Art

[0002] In many fields such as industrial equipment, transportation vehicles, and buildings, noise pollution is an urgent problem to be solved. Traditional noise reduction materials often have the situation that a single performance is prominent while the comprehensive performance is insufficient. For example, the metal substrate has high strength but limited sound insulation effect, the rubber has certain sound absorption and shock absorption performance but insufficient mechanical strength, and the wet laid mat has its unique advantages in sound absorption but lacks sufficient structural support. Therefore, it is of great significance to develop a composite material that can combine the advantages of the wet laid mat, the metal substrate and the rubber, has good noise reduction performance and stable mechanical properties. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the above-mentioned existing technologies, and to provide a composite material of a wet laid mat, a metal substrate and a rubber layer for noise reduction, which has good noise reduction performance, high strength and stable structural characteristics, and meets the various requirements for noise reduction materials in industry and life.

[0004] Another purpose of the present invention is to provide a preparation method of the composite material for noise reduction.

[0005] The technical solution provided by the present invention is: a composite material for noise reduction, which is characterized in that it is composed of a wet laid mat, a metal substrate and a rubber layer in combination; the wet laid mat, the metal substrate and the rubber layer are combined in the order of rubber layer, adhesive, metal substrate, adhesive, wet laid mat; its preparation method: on a flat vulcanizer or a hot press, first place a layer of rubber layer at the bottom of the mold, then place the metal substrate with adhesive coated on both sides on the rubber layer, then place the metal substrate with adhesive coated on both sides on the rubber layer again, and then lay a layer of wet laid mat; close the mold, apply pressure, and heat at the same time for vulcanization to form a composite material of a wet laid mat, a metal substrate and a rubber layer.

[0006] Furthermore, the wet laid mat is made of the following raw materials in parts by weight: 30 - 50 parts of plant fiber, 20 - 30 parts of mineral fiber, 10 - 20 parts of binder, 5 - 15 parts of sound absorption additive; the plant fiber is wood fiber or hemp fiber; the mineral fiber is rock wool fiber or glass fiber; the binder is water-soluble polyvinyl alcohol or starch-based binder; the sound absorption additive is porous vermiculite powder or expanded perlite powder; the thickness of the wet laid mat is 0.1 - 1 mm.

[0007] Further, the plant fiber has a length of 2-5 mm and a diameter of 10-50 μm; the mineral fiber has a length of 3-6 mm and a diameter of 5-30 μm; the sound-absorbing additive has a particle size of 10-100 μm.

[0008] Further, the metal substrate is a thin metal substrate with a thickness of 0.1-1 mm, and the material is carbon steel or stainless steel.

[0009] Further, the rubber layer is made of a blend rubber of 70-90 parts of nitrile rubber, 5-15 parts of natural rubber and 5-15 parts of styrene-butadiene rubber by weight; the hardness of the rubber is 40-70 Shore A, and 10-30 parts by weight of a sound-absorbing filler is added to the rubber. The sound-absorbing filler is calcium carbonate or carbon black; the particle size of the sound-absorbing filler is 20-80 μm; the thickness of the rubber layer is 0.1-1 mm.

[0010] Further, the binder is a rubber-based binder or an epoxy resin-based binder.

[0011] A method for preparing a sound-absorbing and noise-reducing composite material according to the present invention is characterized in that it includes the following steps: a Preparation of a wet laid sheet; adding plant fibers and mineral fibers to a beater, adding water for beating treatment; dissolving or dispersing the binder and the sound-absorbing additive in water to form a uniform solution or suspension; mixing the above fiber slurry with the mixture of the binder and the sound-absorbing additive, stirring evenly, and forming on a paper machine through a wet laid process to form a wet laid sheet, and then performing a drying treatment; b Treatment of the metal substrate; performing surface cleaning on the metal substrate to remove oil stains and impurities, and then performing phosphating treatment or sandblasting treatment; c Preparation of the rubber layer; kneading the rubber raw materials in an open mill or an internal mixer, and when the rubber reaches a plastic state, adding the sound-absorbing filler and continuing to knead to make the filler evenly dispersed in the rubber; then forming the kneaded rubber into a rubber sheet with a predetermined thickness through an extruder or a calender, that is, the rubber layer; d Composite molding of the composite material; on a flat vulcanizer or a hot press, first place a layer of rubber layer at the bottom of the mold, then place the metal substrate coated with the adhesive on both sides on the rubber layer, and finally cover a wet laid sheet on it; close the mold, apply a certain pressure, the pressure is 5-10 MPa, and at the same time heat, the heating temperature is 140-180 °C, and the vulcanization time is 10-30 minutes to form a composite material of a wet laid sheet, a metal substrate and a rubber.

[0012] Advantages of the present invention: The composite material has remarkable effects in noise reduction. The sound absorption coefficient can reach 0.6 - 0.9 in the medium and high frequency bands, and the noise reduction amount can reach 15 - 30 dB(A). At the same time, it has good mechanical properties, with a tensile strength of 10 - 20 MPa, a flexural strength of 20 - 30 MPa, and an impact strength of 5 - 10 kJ / m², which can meet the requirements of various actual application scenarios. Brief Description of the Drawings

[0013] Figure 1 It is a schematic structural diagram of the present invention. Detailed Embodiments

[0014] For better understanding and implementation, the present invention will be described in detail below with reference to the drawings.

[0015] Example 1, as Figure 1 shown, a noise-reducing composite material is composed of a wet-laid board 1, a metal substrate 2, and a rubber layer 3; the wet-laid board 1, the metal substrate 2, and the rubber layer 3 are compounded in the order of the rubber layer 3, adhesive, metal substrate 2, adhesive, wet-laid board 1; the specific preparation method is as follows: Preparation of the wet-laid board: Accurately weigh 40 Kg of plant fibers, 25 Kg of mineral fibers, 15 Kg of binder, and 10 Kg of sound absorption additive; the plant fibers can be selected from wood fibers, hemp fibers, etc., with a length of 2 - 5 mm and a diameter of 10 - 50 μm, which can provide the basic skeleton structure of the wet-laid board and have certain flexibility and sound absorption performance; the mineral fibers can be rock wool fibers, glass fibers, etc., with a length of 3 - 6 mm and a diameter of 5 - 30 μm, which helps to enhance the heat resistance and strength of the wet-laid board and also plays a certain role in blocking and scattering the propagation of sound; the binder is selected from water-soluble polyvinyl alcohol or starch-based binders to ensure that the fibers can be effectively bonded together during the forming process of the wet-laid board to form a stable sheet structure; the sound absorption additive can be selected from porous vermiculite powder, expanded perlite powder, etc., with a particle size of 10 - 100 μm, which can effectively absorb and scatter sound waves and improve the sound absorption and noise reduction ability of the wet-laid board; the thickness of the wet-laid board is 0.1 - 1 mm; Add the plant fibers and mineral fibers to a beater, add 2000 kg of appropriate amount of water for beating treatment, and the beating time is 30 - 60 minutes to fully disperse and refine the fibers; dissolve or disperse the binder and the sound absorption additive in water to form a uniform solution or suspension; mix the above fiber slurry with the mixture of the binder and the sound absorption additive, stir evenly, and then form a wet-laid board on a paper machine through the wet-laid process, and then carry out drying treatment, with a drying temperature of 80 - 120 °C and a drying time of 10 - 30 minutes to control the water content of the wet-laid board at 5% - 10%; Treatment of the metal substrate: The metal substrate uses a thin metal substrate with a thickness of 0.1 - 1 mm, and its material can be carbon steel, stainless steel, etc.; the metal substrate is surface cleaned to remove oil and impurities, and then phosphating treatment or sandblasting treatment is carried out to enhance its bonding performance with the rubber layer. Conventional phosphating solution is used for phosphating treatment, and the treatment time is 10 - 20 minutes. Quartz sand with a particle size of 0.5 - 1 mm is used for sandblasting treatment, and the spraying pressure is 0.3 - 0.6 Mpa; the metal substrate mainly plays a role of providing structural support and enhancing the overall strength in the composite material, and at the same time can also reflect a part of the sound wave to reduce the sound penetration; Preparation of the rubber layer: The rubber layer is made of a blend rubber of 80 Kg of nitrile rubber, 10 Kg of natural rubber and 10 Kg of styrene-butadiene rubber; the hardness of the rubber is 40 - 70 Shore A, and 20 Kg of sound-absorbing filler is added to the rubber. The sound-absorbing filler can be selected from calcium carbonate, carbon black, etc., and the particle size of the sound-absorbing filler is 20 - 80 μm. These fillers can increase the internal friction of the rubber and the scattering of sound waves, and improve the sound-absorbing effect of the rubber; the thickness of the rubber layer is 0.1 - 1 mm; The rubber raw materials are kneaded in an open mill or a internal mixer. When the rubber reaches a plastic state, the sound-absorbing filler is added and kneaded for another 10 - 20 minutes to make the filler evenly dispersed in the rubber; then the kneaded rubber is formed into a rubber sheet with a predetermined thickness through an extruder or a calender, that is, the rubber layer; Composite molding of the composite material: On a flat vulcanizer or a hot press, first place a layer of rubber layer 3 at the bottom of the mold, then place the metal substrate 2 with both sides coated with an adhesive on the rubber layer 3, and finally cover a layer of forming board 1 on it; the adhesive can be selected from rubber adhesives or epoxy resin adhesives to ensure tight bonding between layers; close the mold, apply a certain pressure, the pressure is 5 - 10 MPa, and at the same time heat, the heating temperature is 140 - 180 °C, and the vulcanization time is 10 - 30 minutes to vulcanize and form the rubber. The layers are firmly bonded through the adhesive to form a forming board, metal substrate and rubber composite material; when the sound wave passes through the composite material, it is first absorbed and scattered by the sound-absorbing materials of the rubber layer and the forming board layer, and part of the sound wave is reflected by the metal substrate layer. After being processed by the forming board layer and the rubber layer, the sound insulation and noise reduction effect is greatly improved. At the same time, the metal substrate layer ensures the overall strength and stability of the material, making it applicable to various complex working conditions.

[0016] The prepared composite material is subjected to sound absorption and noise reduction performance tests and mechanical property tests; for the sound absorption and noise reduction performance tests, acoustic test equipment such as the impedance tube method or reverberation chamber method can be used to test the sound absorption coefficient and noise reduction amount of the composite material for sound waves of different frequencies; the mechanical property tests include tensile strength tests, flexural strength tests, impact strength tests, etc., and are carried out in accordance with relevant national standards or industry standards. The test results show that the composite material of the present invention has significant effects in sound absorption and noise reduction, the sound absorption coefficient can reach 0.6 - 0.9 in the medium and high frequency bands, the noise reduction amount can reach 15 - 30 dB (A), and at the same time has good mechanical properties, the tensile strength is 10 - 20 MPa, the flexural strength is 20 - 30 MPa, and the impact strength is 5 - 10 kJ / m², which can meet the requirements of various actual application scenarios.

[0017] Example 2 is the same as Example 1, except that the wet laid mat is made of 30 Kg of plant fiber, 30 Kg of mineral fiber, 10 Kg of binder, and 5 Kg of sound absorption additive; the rubber layer is made of a blend rubber of 70 Kg of nitrile rubber, 15 Kg of natural rubber, and 5 Kg of styrene-butadiene rubber, and 10 Kg of sound absorption filler is added to the rubber.

[0018] Example 3 is the same as Example 1, except that the wet laid mat is made of 50 Kg of plant fiber, 20 Kg of mineral fiber, 20 Kg of binder, and 15 Kg of sound absorption additive; the rubber layer is made of a blend rubber of 90 Kg of nitrile rubber, 5 Kg of natural rubber, and 15 Kg of styrene-butadiene rubber, and 30 Kg of sound absorption filler is added to the rubber.

[0019] It should be understood that the technical features not elaborated in detail in this specification all belong to the prior art. Although the embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Those skilled in the art can, under the inspiration of the present invention, without departing from the spirit and scope protected by the present invention and the claims, make more forms, and these all fall within the protection scope of the present invention.

Claims

1. A sound-absorbing and noise-reducing composite material, characterized in that, It is composed of a picked-up board (1), a metal substrate (2) and a rubber layer (3) in a composite manner; the picked-up board (1), the metal substrate (2) and the rubber layer (3) are compounded in the order of the rubber layer (3), adhesive, metal substrate (2), adhesive, and picked-up board (1); its preparation method: on a flat vulcanizer or a hot press, first place a layer of rubber layer (3) at the bottom of the mold, then place the metal substrate (2) with adhesive coated on both sides on the rubber layer (3), and then place the metal substrate (2) with adhesive coated on both sides on the rubber layer, and then lay a layer of picked-up board (1); close the mold, apply pressure, and heat at the same time for vulcanization to form a composite material of the picked-up board, the metal substrate and the rubber layer.

2. The noise-reducing composite material according to claim 1, wherein, The picked-up board (1) is made of the following raw materials in parts by weight: 30-50 parts of plant fiber, 20-30 parts of mineral fiber, 10-20 parts of binder, and 5-15 parts of sound-absorbing additive; the plant fiber is wood fiber or hemp fiber; the mineral fiber is rock wool fiber or glass fiber; the binder is water-soluble polyvinyl alcohol or starch-based binder; the sound-absorbing additive is porous vermiculite powder or expanded perlite powder; the thickness of the picked-up board (1) is 0.1-1 mm.

3. The noise-reducing composite material according to claim 2, characterized in that, The length of the plant fiber is 2-5 mm, and the diameter is 10-50 μm; the length of the mineral fiber is 3-6 mm, and the diameter is 5-30 μm; the particle size of the sound-absorbing additive is 10-100 μm.

4. A sound-absorbing and noise-reducing composite material according to claim 1, characterized in that, The metal substrate (2) uses a thin metal substrate with a thickness of 0.1-1 mm, and the material is carbon steel or stainless steel.

5. A sound-absorbing and noise-reducing composite material according to claim 1, characterized in that, The rubber layer (3) is made of a blend rubber of 70-90 parts of nitrile rubber, 5-15 parts of natural rubber and 5-15 parts of styrene-butadiene rubber by weight; the hardness of the rubber is 40-70 Shore A, and 10-30 parts by weight of sound-absorbing filler is added to the rubber, and the sound-absorbing filler is calcium carbonate or carbon black; the particle size of the sound-absorbing filler is 20-80 μm; the thickness of the rubber layer (3) is 0.1-1 mm.

6. The composite material for noise reduction according to claim 1, characterized in that, The binder is a rubber-based binder or an epoxy resin-based binder.

7. The preparation method of any one of the sound-absorbing and noise-reducing composite materials according to claims 1-6, characterized in that, It includes the following steps: a Preparation of the picked-up board; add plant fiber and mineral fiber to a beater, add water for beating treatment; dissolve or disperse the binder and the sound-absorbing additive in water to make a uniform solution or suspension; mix the above fiber slurry with the mixture of the binder and the sound-absorbing additive, stir evenly, and form a picked-up board by the picking process on a paper machine, and then carry out drying treatment; b Treatment of the metal substrate; clean the surface of the metal substrate to remove oil stains and impurities, and then carry out phosphating treatment or sandblasting treatment; c Preparation of the rubber layer; knead the rubber raw materials in an open mill or a internal mixer, and when the rubber reaches a plastic state, add the sound-absorbing filler and continue kneading to make the filler evenly dispersed in the rubber; then form the kneaded rubber into a rubber sheet with a predetermined thickness through an extruder or a calender, that is, the rubber layer; Composite molding of d composite materials; on a flat vulcanizer or hot press, first place a layer of rubber on the bottom of the mold, then place a metal substrate coated with adhesive on both sides on the rubber layer, and finally cover it with a couch roll; close the mold, apply a certain pressure, the pressure is 5-10 MPa, heat at the same time, the heating temperature is 140-180 °C, and the vulcanization time is 10-30 minutes to form a couch roll, metal substrate and rubber composite material.

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