Acoustic enhancement material, preparation method thereof, loudspeaker, and electronic equipment

Abstract

The present invention provides an acoustic enhancement material, a preparation method thereof, a loudspeaker, and an electronic device. The acoustic enhancement material has micropores, mesopores, and macropores, and comprises silica aerogel reinforced with a fibrous structure-reinforcing filler and SSZ-13 zeolite molecular sieve, the SSZ-13 zeolite molecular sieve being chemically bonded to the interior and surface of the silica aerogel reinforced with the fibrous structure-reinforcing filler. The acoustic enhancement material provided by the present invention exhibits excellent low-frequency acoustic improvement, high strength, and low water absorption.

Description

Technical Field

[0001] The invention relates to an acoustic enhancement material and a preparation method thereof, a loudspeaker and an electronic device, and belongs to the technical field of materials, in particular to the technical field of electronic acoustic materials. Background Art

[0002] Speaker miniaturization has become a mainstream trend and is attracting increasing attention. However, the acoustic quality of micro speakers deteriorates as their size decreases. Porous materials have a very high specific surface area and excellent adsorption-storage-desorption properties for air molecules. They are often used in micro speakers to improve low-frequency acoustics. When the speaker diaphragm vibrates, it changes the pressure in the speaker's rear cavity, compressing the air and forcing it into the porous material. When the pressure decreases, the air molecules adsorbed and stored in the porous material are released, thereby changing the rigidity of the air in the speaker's rear cavity and improving low-frequency acoustics.

[0003] CN103098490A discloses a zeolite molecular sieve with a silicon-aluminum mass ratio of 200 or greater as a low-frequency improvement material for loudspeakers. The zeolite molecular sieve is formed into 0.2-0.9mm granules using an organic adhesive. The granules contain pore structures of varying sizes and offer excellent acoustic improvement. However, the introduction of the organic adhesive can lead to the generation of volatile organic molecules over long periods of operation. If these organic molecules are not expelled promptly, they will be adsorbed by the zeolite molecular sieve in the granules, blocking some of the pores and reducing the acoustic improvement effect.

[0004] CN109874089A discloses the use of SiO2 aerogel as a sound-absorbing material to improve the acoustic performance of loudspeakers. The sound-absorbing material contains pore structures such as mesopores and micropores. When a high-molecular-weight polymer binder is introduced, there is also the problem of pore clogging by small organic volatile molecules. Furthermore, SiO2 aerogel is an amorphous porous material, and the proportion of micropores, mesopores, and macropores is difficult to control, resulting in a significant degree of randomness during the synthesis process.

[0005] In summary, in the existing technology, the polymer adhesive introduced during the molding process of porous materials will produce volatile organic small molecules during long-term operation. These organic small molecules are easily adsorbed by the porous material, blocking the pore structure and causing performance degradation; in addition, the pore distribution of amorphous materials is difficult to control.

[0006] Therefore, providing a new acoustic enhancement material and a preparation method thereof, as well as a loudspeaker and an electronic device has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] In order to solve the above-mentioned shortcomings and deficiencies, an object of the present invention is to provide an acoustic enhancement material.

[0008] Another object of the present invention is to provide a method for preparing the above-mentioned acoustic enhancement material.

[0009] Yet another object of the present invention is to provide a loudspeaker, wherein at least one of the loudspeaker front cavity, the loudspeaker rear cavity, the housing and the sound-emitting unit is equipped with the acoustic enhancement material described above.

[0010] Yet another object of the present invention is to provide an electronic device comprising the above-mentioned speaker.

[0011] In order to achieve the above objectives, on the one hand, the present invention provides an acoustic enhancement material, wherein the acoustic enhancement material has micropores, mesopores and macropores at the same time, and includes silica aerogel reinforced with fibrous structure reinforcing fillers and SSZ-13 zeolite molecular sieve, and the SSZ-13 zeolite molecular sieve is bonded to the interior and surface of the silica aerogel reinforced with the fibrous structure reinforcing filler through chemical bonds (chemical bonds formed during the crystallization process).

[0012] As a specific embodiment of the above-mentioned acoustic enhancement material of the present invention, the mass ratio of the SSZ-13 zeolite molecular sieve to the silica aerogel reinforced with the fibrous structure reinforcing filler is 1:1-1:4.

[0013] As a specific embodiment of the acoustic enhancement material described above, the SSZ-13 zeolite molecular sieve includes a pure silicon structure molecular sieve, a silicon-alumina structure molecular sieve, a silicon-phosphorus-alumina structure molecular sieve, or a phosphorus-alumina structure molecular sieve. To ensure strong bonding between the molecular sieve material and the silica aerogel reinforced with the fibrous structure reinforcing filler, the molecular sieve material preferably contains silicon. Specifically, the SSZ-13 zeolite molecular sieve is preferably a pure silicon structure molecular sieve, a silicon-alumina structure molecular sieve, or a silicon-phosphorus-alumina structure molecular sieve.

[0014] When the SSZ-13 zeolite molecular sieve is selected from non-pure silicon structure molecular sieves such as silicon-aluminum structure molecular sieve, silicon-phosphorus-aluminum structure molecular sieve or phosphorus-aluminum structure molecular sieve, the present invention does not impose specific restrictions on the molar ratio of silicon to metal in the SSZ-13 zeolite molecular sieve, such as the silicon-aluminum ratio. For example, when the SSZ-13 zeolite molecular sieve is a silicon-aluminum structure molecular sieve, considering that the SSZ-13 zeolite molecular sieve with a lower silicon-aluminum ratio has a good affinity for water molecules, in order to make the acoustic enhancement material have excellent water absorption resistance, in practical applications, it can be considered to use an SSZ-13 zeolite molecular sieve with a higher silicon-aluminum ratio (the molar ratio of silicon and aluminum atoms is not less than 100).

[0015] In addition, for the silicon-aluminum structure molecular sieve, due to the requirement of structural electrical neutrality, extra-framework cations can be introduced, and the extra-framework cations can be one or a combination of hydrogen ions, monovalent metal ions, divalent metal ions and multivalent metal ions. The present invention does not make specific requirements on the method of introducing cations outside the framework of the silicon-aluminum structure molecular sieve. The specific introduction method can be reasonably selected according to the actual operation needs on site and / or the specific substance of the cation, as long as it can achieve the purpose of introducing cations outside the framework of the silicon-aluminum structure molecular sieve.

[0016] In a specific embodiment of the acoustic enhancement material described above, the content of the fibrous structure-reinforcing filler is 1-8%, based on the total weight of SiO2 in the silica aerogel reinforced with the fibrous structure-reinforcing filler being 100%. Excessive content of the fibrous structure-reinforcing filler may increase the water absorption of the acoustic enhancement material, thereby affecting its acoustic performance.

[0017] As a specific embodiment of the acoustic enhancement material described above, the silica aerogel reinforced with the fibrous structure reinforcing filler comprises a fibrous structure reinforcing filler and silica aerogel, and the fibrous structure reinforcing filler is uniformly dispersed in the silica aerogel.

[0018] As a specific embodiment of the above-mentioned acoustic enhancement material of the present invention, the size of the silica aerogel reinforced with the fibrous structure reinforcing filler is 35-50 mesh.

[0019] As a specific embodiment of the acoustic enhancement material described above in the present invention, the fibrous structure reinforcing filler includes one or a combination of halloysite, boehmite, mullite and asbestos.

[0020] The present invention does not impose specific requirements on the morphology of the acoustic enhancement material. The silica aerogel reinforced with the fibrous structure reinforcing filler can exhibit different appearances, and the appropriate specific form can be selected based on the desired use (e.g., the shape of the speaker back cavity). For example, the appearance can be irregular, such as one or a combination of irregular particles, irregular blocks, irregular sheets, irregular fibers, and irregular polyhedrons; or regular, such as one or a combination of regular spherical particles, nearly spherical regular particles, regular blocks, regular sheets, and regular fibers. In some embodiments, large-scale acoustic enhancement materials can be formed by bonding prepared nano-metastructured particles, i.e., smaller-sized acoustic enhancement materials.

[0021] On the other hand, the present invention also provides a method for preparing the above-mentioned acoustic enhancement material, wherein the preparation method comprises:

[0022] Dissolving a silicon source, an alkali source and a mineralizer in deionized water to obtain a molecular sieve mother liquor;

[0023] The silica aerogel reinforced with a fibrous structure reinforcing filler is added to the molecular sieve mother solution and mixed evenly, the obtained mixed solution is crystallized, and finally the crystallized product is washed, dried and calcined to obtain the acoustic enhancement material.

[0024] In one embodiment of the above-described preparation method of the present invention, the molecular sieve mother liquor further contains a template. The silica aerogel reinforced with a fibrous structure-reinforced filler exhibits excellent thermal stability, and the structure of the silica aerogel is not destroyed even during the introduction of the template and subsequent high-temperature removal of the template.

[0025] As a specific embodiment of the preparation method described above, the calcination temperature is no higher than 700°C. Furthermore, the present invention does not impose specific requirements on the specific materials and amounts of the silicon source, alkali source, mineralizer, and template used in the preparation of the acoustic enhancement material; these materials can be reasonably selected and adjusted based on actual site needs. For example, in some embodiments of the present invention, the template can be selected from N,N,N-trimethyl-1-adamantyl ammonium hydroxide.

[0026] As a specific embodiment of the above-mentioned preparation method of the present invention, the preparation method of the silica aerogel reinforced with fibrous structure reinforcing filler comprises:

[0027] A silicon source, a cosolvent and deionized water are mixed to obtain a first mixed liquid, an acidic catalyst is added to the first mixed liquid to hydrolyze the silicon source to produce a sol, a gel accelerator and a fibrous structure reinforcing filler are then added to the sol and mixed evenly to obtain a second mixed liquid, an alkaline catalyst is then added to the second mixed liquid to form a wet gel, and finally the wet gel is aged and dried to obtain the silica aerogel reinforced with the fibrous structure reinforcing filler.

[0028] As a specific embodiment of the preparation method described above in the present invention, the silicon source used in preparing the silica aerogel reinforced with fibrous structure reinforcing fillers is organic silicon and / or inorganic silicon, wherein the organic silicon includes one or a combination of tetraethyl orthosilicate (TEOS), methyl orthosilicate (TMOS), polysiloxane (PEDS), methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES) and silsesquioxane (POSS), and the inorganic silicon includes one or a combination of silica sol, water glass, sodium silicate and silicon tetrachloride.

[0029] As a specific embodiment of the preparation method described above of the present invention, the acidic catalyst used in the preparation of the silica aerogel reinforced with a fibrous structure reinforcing filler is an organic acidic catalyst and / or an inorganic acidic catalyst, wherein the organic acidic catalyst includes one or a combination of formic acid, acetic acid, oxalic acid, propionic acid, malonic acid, succinic acid, glutaric acid, citric acid, monosodium citrate, oleic acid and oxalic acid, and the inorganic acidic catalyst includes one or a combination of hydrochloric acid, bromic acid, boric acid, sulfuric acid, sulfurous acid, nitric acid, nitrous acid, phosphoric acid, phosphorous acid, metaphosphorous acid, ammonium bisulfate, sodium bisulfate, potassium bisulfate, ferric acid and permanganic acid.

[0030] As a specific embodiment of the preparation method described above of the present invention, the alkaline catalyst used in the preparation of the silica aerogel reinforced with a fibrous structure reinforcing filler is an organic alkaline catalyst and / or an inorganic alkaline catalyst, wherein the organic alkaline catalyst includes one or a combination of methylamine, ethylamine, ethylenediamine, propylamine, propylenediamine, isopropylamine, diisopropylamine, butylamine, cyclohexylamine, hexamethylenediamine, melamine and imidazole, and the inorganic alkaline catalyst includes one or a combination of ammonia water, hydrazine hydrate, sodium bicarbonate, potassium bicarbonate, sodium carbonate, potassium carbonate, potassium oxalate, sodium oxalate, sodium formate and sodium acetate.

[0031] As a specific embodiment of the preparation method described above of the present invention, the cosolvent used in preparing the silica aerogel reinforced with fibrous structure reinforcing fillers includes one or a combination of methanol, ethanol, ethylene glycol, propanol, propylene glycol, glycerol, butanol and butanediol.

[0032] As a specific embodiment of the preparation method described above of the present invention, the gelling accelerator used in preparing the silica aerogel reinforced with fibrous structure reinforcing fillers includes one or a combination of formamide, acetamide, methylacetamide, methylenediformamide, terephthalamide and phthalamide.

[0033] As a specific embodiment of the above-mentioned preparation method of the present invention, when preparing silica aerogel reinforced with fibrous structure reinforcing fillers, the temperature of the hydrolysis process is 40-80° C. and the time is 2-48 hours.

[0034] As a specific embodiment of the above preparation method of the present invention, the crystallization temperature is 60-200° C. and the time is 1 day to 10 days.

[0035] As shown above, the preparation method of the acoustic enhancement material includes the preparation of silica aerogel reinforced with a fibrous structure reinforcing filler and the preparation of the acoustic enhancement material. Among them, the silica aerogel reinforced with a fibrous structure reinforcing filler is prepared by a normal pressure drying method. Its preparation process generally includes the dissolution, hydrolysis, polycondensation, aging and drying of the silicon source. In the initial stage of the reaction, the silicon source is hydrolyzed to obtain the active monomer silicic acid. A certain amount of fibrous structure reinforcing filler is added while stirring. Then, the silicic acid is polycondensed to form a polymer (sol) with silicon oxygen (-Si-O-Si-) as the main body, which is then cross-linked to form a gel skeleton with a three-dimensional network structure. There are a large number of pores between the gel skeletons, which are filled with solvent molecules such as ethanol and water. The obtained wet gel is first aged, and then the liquid solvent in the gel is replaced by a gaseous substance through a drying process, thereby obtaining a silica aerogel reinforced with a fibrous structure reinforcing filler. In addition, when preparing silica aerogel reinforced with fibrous structure reinforcing fillers, the wet gel can be doped to improve its high-temperature stability or hydrophobically modified to increase its hydrophobicity as needed. The present invention does not make specific requirements on the specific operations of the doping process and the hydrophobic modification process, the process parameters used, the doping substances and the hydrophobic modifiers, etc., and can be reasonably adjusted and selected according to actual needs.

[0036] Furthermore, based on actual on-site operational needs, the silica aerogel reinforced with fibrous structural reinforcing fillers can be crushed and sieved to obtain particles (e.g., 30-50 mesh particles). These particles are then placed in a polyurethane ball mill for rolling milling. The collision and friction between the particles removes sharp corners, resulting in nearly spherical silica aerogel particles reinforced with fibrous structural reinforcing fillers for later use. After ball milling, the acoustic enhancement material appears as microspheres of appropriate size, eliminating the need for subsequent molding processes and avoiding the introduction of molding adhesives.

[0037] Then, silica aerogel reinforced with a fibrous structure reinforcing filler having an elemental composition similar to that of the molecular sieve is used as a crystallization carrier, which is immersed in a molecular sieve mother liquor containing a silicon source, an alkali source and a mineralizer, and stirred for a sufficiently long time so that the molecular sieve mother liquor can fully soak the silica aerogel; the molecular sieve mother liquor containing the silica aerogel is then transferred to a molecular sieve crystallization device, and appropriate crystallization conditions are set to carry out a crystallization reaction; after the reaction is completed, a microporous-mesoporous-macroporous nano-micro meta-structure acoustic material with regular microporous channels, namely the acoustic enhancement material, can be obtained.

[0038] On the other hand, the present invention also provides a speaker, comprising one or more sound-emitting units and one or more shells, wherein the one or more sound-emitting units are combined with the one or more shells to form a speaker back cavity, wherein at least one of the speaker front cavity, speaker back cavity, shell and sound-emitting unit is equipped with the acoustic enhancement material described above.

[0039] As a specific embodiment of the above-mentioned loudspeaker of the present invention, the loudspeaker is a micro loudspeaker.

[0040] As a specific embodiment of the above-mentioned loudspeaker of the present invention, the sound-emitting unit is an acoustic sensor or the like.

[0041] As a specific embodiment of the speaker described above in the present invention, the acoustic enhancement material can be filled in the rear cavity of the speaker or adhered to the inner wall of the rear cavity of the speaker; the acoustic enhancement material can also be filled in the front cavity of the speaker or adhered to the inner wall of the front cavity of the speaker; the acoustic enhancement material can also be adhered to the inner wall or outer wall of the shell; the acoustic enhancement material can also be adhered to the back of the magnetic bowl of the sound unit and other positions.

[0042] In yet another aspect, the present invention further provides an electronic device, wherein the electronic device includes the above-mentioned speaker.

[0043] As a specific embodiment of the electronic device described above in the present invention, the electronic device includes a smart phone, TWS earphones, headphones, smart glasses, smart watches, VR devices, AR devices, tablet computers or thin and light laptops, etc.

[0044] Compared with the prior art, the present invention can achieve the following beneficial technical effects:

[0045] Compared to amorphous materials, SSZ-13 zeolite molecular sieve is an inorganic microporous crystalline structure with a regular pore distribution. The present invention combines SSZ-13 zeolite molecular sieve with silica aerogel reinforced with a fibrous structure-reinforced filler to introduce a regular microporous structure into amorphous porous materials such as aerogels, thereby forming a metamaterial with a microporous-mesoporous-macroporous nanostructure with regular micropores. In other words, the acoustic enhancement material provided by the present invention combines the regular microporous structure of SSZ-13 zeolite molecular sieve with the mesoporous and macroporous structures and lightweight advantages of SiO2 aerogel.

[0046] The acoustic enhancement material provided by the present invention has a pore structure of three scale levels: macropores, mesopores, and micropores. That is, it is an acoustic enhancement material with a nano-micro superstructure. The presence of these pores makes the nano-micro superstructure material have a very large specific surface area. Compared with non-porous materials, these pores can provide a larger area and more sites for the adsorption of air molecules. In this acoustic enhancement material, the pores of the macropores are generally larger than 50nm, the size of the mesopores is between 2-50nm, and the size of the micropores is less than 2nm; and the size of the molecules in the air is all below 1nm. Therefore, the macropores and large-sized mesopores in the acoustic enhancement material can allow air molecules to freely enter the pore structure, while the micropores and small-sized mesopores will affect the free diffusion of air molecules. During the diffusion process of air molecules, they inevitably come into contact with the atoms that constitute the pore wall and are adsorbed. When the loudspeaker diaphragm vibrates, the diaphragm compresses inward, which increases the pressure in the rear cavity of the loudspeaker, thereby changing the motion state of air molecules, causing them to quickly enter the porous material, increasing the probability of contact between air molecules and the pore walls, and thus causing the air molecules to be adsorbed; when the diaphragm vibrates outward, the pressure in the rear cavity of the loudspeaker decreases, and the adsorbed air molecules leave the pore walls due to the pressure difference, changing from an adsorption state to a desorption state, and diffuse into large pores or large-sized mesopores; the vibration of the diaphragm causes the pressure in the rear cavity of the loudspeaker to change, thereby causing the state of air molecules in the acoustic enhancement material to continuously change, that is, the state change process is diffusion-adsorption-desorption-diffusion, thereby changing the rigidity of the air in the rear cavity of the loudspeaker, thereby achieving the effect of improving the low-frequency acoustic effect.

[0047] Compared to other molecular sieves with one-dimensional pore structures, the SSZ-13 zeolite molecular sieve used in the present invention has a three-dimensional 8-membered ring pore structure. After crystallization on the surface and inside the silica aerogel reinforced with fibrous structure-reinforcing fillers, it significantly improves the porosity, accessible volume, and specific surface area of ​​the resulting acoustic enhancement material. Therefore, the acoustic enhancement material provided by the present invention significantly improves low-frequency acoustics compared to existing acoustic enhancement materials.

[0048] In addition, the acoustic enhancement material provided by the present invention contains silica aerogel reinforced with a fibrous structure reinforcing filler. The introduction of the fibrous structure reinforcing filler enhances the structural strength of the SiO2 aerogel. Moreover, the present invention does not require a subsequent molding process when preparing the acoustic enhancement material, thus avoiding the introduction of a molding adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 This is a scanning electron microscope image of the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 1 of the present invention.

[0051] Figure 2 This is a scanning electron microscope image of the acoustic enhancement material prepared in Example 1 of the present invention.

[0052] Figure 3 This is a scanning electron microscope image of the acoustic enhancement material prepared in Comparative Example 1.

[0053] Figure 4 This is a micropore distribution diagram of the acoustic enhancement material prepared in Example 1 of the present invention.

[0054] Figure 5 This is the mesopore distribution diagram of the acoustic enhancement material prepared in Example 1 of the present invention.

[0055] Figure 6 This is the macropore distribution diagram of the acoustic enhancement material prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0056] It should be noted that the term "comprise" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or apparatus.

[0057] The "range" disclosed in the present invention is given in the form of a lower limit and an upper limit. It can be one or more lower limits, and one or more upper limits respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower limit and upper limit define the boundaries of a particular range. All ranges defined in this way are combinable, i.e., any lower limit can be combined with any upper limit to form a range. For example, a range of 60-120 and 80-110 is listed for a particular parameter, and it is understood that a range of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​listed are 1 and 2, and the maximum range values ​​listed are 3, 4, and 5, then the following ranges can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5.

[0058] In the present invention, unless otherwise specified, the numerical range "ab" is an abbreviation for any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" are listed in this invention, and "0-5" is merely an abbreviation for these numerical combinations.

[0059] In the present invention, unless otherwise specified, all embodiments and preferred embodiments mentioned in the present invention can be combined with each other to form a new technical solution.

[0060] In the present invention, unless otherwise specified, all technical features and preferred features mentioned in the present invention can be combined with each other to form a new technical solution.

[0061] In the present invention, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method comprising steps (a) and (b) indicates that the method may comprise steps (a) and (b) performed sequentially, or may comprise steps (b) and (a) performed sequentially. For example, the method further comprising step (c) indicates that step (c) may be added to the method in any order, for example, the method may comprise steps (a), (b) and (c), or may comprise steps (a), (c) and (b), or may comprise steps (c), (a) and (b), etc.

[0062] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the attached table, drawings and examples. The following embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0063] Preparation Example 1

[0064] This preparation example provides a halloysite fiber-reinforced silica aerogel microsphere, which is prepared by a preparation method comprising the following specific steps:

[0065] With tetraethyl orthosilicate as silicon source, deionized water as solvent, anhydrous ethanol as cosolvent (to increase the solubility of tetraethyl orthosilicate in deionized water), oxalic acid as acidic catalyst, ammonia as alkaline catalyst and formamide as gel accelerator. First, deionized water, anhydrous ethanol and tetraethyl orthosilicate are weighed and mixed in a molar ratio of 10:5:1. The mixed solution is transferred to a 45°C water bath. During the stirring process, a 0.1M oxalic acid solution is added dropwise until the pH is 2. The stirring is continued for 30 minutes. During this process, the tetraethyl orthosilicate is hydrolyzed to produce a sol. Then, formamide is added dropwise. The molar ratio of formamide to tetraethyl orthosilicate is 0.7:1. Stirring is carried out while adding formamide for 5-10 minutes. During the stirring process, 3wt% of halloysite fibers with a length of 800nm-1.2μm (the amount is calculated based on the SiO2 content in the tetraethyl orthosilicate) are added and mixed evenly. Halloysite is a kind of aluminum oxide. The aluminosilicate material composed of and silicon oxide has high thermal stability and corrosion resistance; fibrous halloysite is added to the mother liquor used to prepare silica aerogel, and it can participate in the sol-gel process of silica aerogel; then, a 0.5M ammonia solution is added until the pH is 7, and after stirring evenly, it is allowed to stand to produce gel, and a wet gel can be obtained by tilting the liquid at 45° without flowing; a 50v% ethanol solution is added to the wet gel until the liquid level is higher than the wet gel, and the wet gel is aged for 24 hours; finally, the aged wet gel is staged-dried, that is, first dried at 60°C for 4 hours and then dried at 80°C for 8 hours to obtain halloysite fiber-reinforced silica aerogel.

[0066] The halloysite fiber-reinforced silica aerogel prepared above is crushed into fine particles; the crushed particles are then sieved with a sieve to obtain microparticles with a size range of 30-40 mesh; the particles are then transferred to a polyimide ball mill for ball milling. During the ball milling process, friction and collision between the particles are used to remove irregular edges and corners of the particles to obtain ellipsoidal or spherical particles; finally, the particles are sieved again to obtain approximately spherical halloysite fiber-reinforced silica aerogel particles / microparticles with a size of 35-50 mesh, which are then placed in a room temperature desiccator for later use.

[0067] Preparation Example 2

[0068] This preparation example provides a 35-50 mesh halloysite fiber-reinforced silica aerogel microsphere. The preparation method thereof differs from that in Preparation Example 1 only in that:

[0069] 10% of halloysite fibers were introduced.

[0070] Comparative Preparation Example 1

[0071] This comparative preparation example provides unreinforced silica aerogel microspheres with a size of 35-50 mesh. The preparation method thereof differs from that in Preparation Example 1 only in that:

[0072] No halloysite fibers were introduced.

[0073] Example 1

[0074] This embodiment provides an acoustic enhancement material, which is prepared by a preparation method comprising the following specific steps:

[0075] Silica sol (SiO2 content of 30wt%) was used as the silicon source, aluminum hydroxide was used as the aluminum source, sodium hydroxide was used as the alkali source and mineralizer, deionized water was used as the solvent, and N,N,N-trimethyl-1-adamantyl ammonium hydroxide was used as the organic template.

[0076] The specific preparation process is as follows: weigh 1.80g of NaOH and dissolve it in 25.0mL of deionized water. Then, under stirring, the obtained solution is added dropwise to 19.04g of 25wt% N,N,N-trimethyl-1-adamantyl ammonium hydroxide solution, and stirred evenly to obtain solution A; 0.078g of aluminum hydroxide is added to solution A, and after the aluminum hydroxide is completely dissolved, a uniform solution B is formed; 30.0g of the above-mentioned silica sol is added to solution B. During the addition process, attention should be paid to adjusting the stirring speed. When a colloidal substance is found in the experiment, the stirring speed should be increased accordingly. When the solution forms a sol, the stirring speed is reduced; then, the silica sol container is washed with 40.0mL of deionized water, and the washing liquid is also added to solution B. Stirring is continued at room temperature for 1.0h to obtain a mixed solution C, that is, the preparation of the molecular sieve mother liquor is completed;

[0077] Subsequently, 15.0 g of the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 1 were added to the molecular sieve mother liquor, and stirring was continued for 1 hour. The resulting mixture was then transferred to a PTFE-lined reactor, aged at 80 ° C for 24 hours, and then crystallized at a constant temperature of 170 ° C for 48 hours. After the crystallization is completed, the resulting crystallized product is centrifuged and washed multiple times to obtain a nano-micro-meta-acoustic material, which is then dried overnight at a temperature of 100 ° C and then calcined at a high temperature of 500 ° C for 6 hours to obtain a nano-micro-meta-acoustic material with the template removed, that is, the acoustic enhancement material. According to the mass change of the material before and after crystallization, the mass ratio of the crystallized molecular sieve, that is, the SSZ-13 zeolite molecular sieve and the halloysite fiber-reinforced silica aerogel microspheres is 2.75:5.

[0078] Example 2

[0079] This embodiment provides an acoustic enhancement material, which is prepared by a preparation method comprising the following specific steps:

[0080] Silica sol (SiO2 content of 30wt%) was used as the silicon source, aluminum hydroxide was used as the aluminum source, sodium hydroxide was used as the alkali source and mineralizer, deionized water was used as the solvent, and N,N,N-trimethyl-1-adamantyl ammonium hydroxide was used as the organic template.

[0081] The specific preparation process is as follows: weigh 1.80g of NaOH and dissolve it in 25.0mL of deionized water. Then, under stirring, the obtained solution is added dropwise to 19.04g of 25wt% N,N,N-trimethyl-1-adamantyl ammonium hydroxide solution, and stirred evenly to obtain solution A; 0.078g of aluminum hydroxide is added to solution A, and after the aluminum hydroxide is completely dissolved, a uniform solution B is formed; 30.0g of the above-mentioned silica sol is added to solution B. During the addition process, attention should be paid to adjusting the stirring speed. When a colloidal substance is found in the experiment, the stirring speed should be increased accordingly. When the solution forms a sol, the stirring speed is reduced; then, the silica sol container is washed with 40.0mL of deionized water, and the washing liquid is also added to solution B. Stirring is continued at room temperature for 1.0h to obtain a mixed solution C, that is, the preparation of the molecular sieve mother liquor is completed;

[0082] Subsequently, 15.0 g of the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 2 were added to the molecular sieve mother liquor, and stirring was continued for 1 hour. The resulting mixture was then transferred to a PTFE-lined reactor, aged at 80 ° C for 24 hours, and then crystallized at a constant temperature of 170 ° C for 48 hours. After the crystallization is completed, the resulting crystallized product is centrifuged and washed multiple times to obtain a nano-micro-meta-acoustic material, which is then dried overnight at a temperature of 100 ° C and then calcined at a high temperature of 500 ° C for 6 hours to obtain a nano-micro-meta-acoustic material with the template removed, that is, the acoustic enhancement material. According to the mass change of the material before and after crystallization, the mass ratio of the crystallized molecular sieve, that is, the SSZ-13 zeolite molecular sieve and the halloysite fiber-reinforced silica aerogel microspheres is 2.78:5.

[0083] Comparative Example 1

[0084] This comparative example provides an acoustic enhancement material, which is prepared by a preparation method comprising the following specific steps:

[0085] Silica sol (SiO2 content of 30wt%) was used as the silicon source, aluminum hydroxide was used as the aluminum source, sodium hydroxide was used as the alkali source and mineralizer, deionized water was used as the solvent, and N,N,N-trimethyl-1-adamantyl ammonium hydroxide was used as the organic template.

[0086] The specific preparation process is as follows: weigh 1.80g of NaOH and dissolve it in 25.0mL of deionized water. Then, under stirring, the obtained solution is added dropwise to 19.04g of 25wt% N,N,N-trimethyl-1-adamantyl ammonium hydroxide solution, and stirred evenly to obtain solution A; 0.078g of aluminum hydroxide is added to solution A, and after the aluminum hydroxide is completely dissolved, a uniform solution B is formed; 30.0g of the above-mentioned silica sol is added to solution B. During the addition process, attention should be paid to adjusting the stirring speed. When a colloidal substance is found in the experiment, the stirring speed should be increased accordingly. When the solution forms a sol, the stirring speed is reduced; then, the silica sol container is washed with 40.0mL of deionized water, and the washing liquid is also added to solution B. Stirring is continued at room temperature for 1.0h to obtain a mixed solution C, that is, the preparation of the molecular sieve mother liquor is completed;

[0087] The obtained molecular sieve mother liquor is then transferred to a PTFE-lined reactor, first aged at 80°C for 24 hours, and then crystallized at a constant temperature of 170°C for 48 hours; after the crystallization is completed, the obtained crystallized product is centrifuged and washed multiple times, then dried overnight at a temperature of 100°C, and then calcined at a high temperature of 500°C for 6 hours to obtain the molecular sieve powder material with the template removed, that is, the acoustic enhancement material.

[0088] Comparative Example 2

[0089] This comparative example provides an acoustic enhancement material, which is prepared by a preparation method comprising the following specific steps:

[0090] Silica sol (SiO2 content of 30wt%) was used as the silicon source, sodium hydroxide was used as the alkaline source and mineralizer, deionized water was used as the solvent, and hexamethyleneimine hydrochloride and N,N,N-trimethyl-1-adamantyl ammonium hydroxide were used as the organic templates.

[0091] The specific preparation process is as follows: 7.0 g of hexamethyleneimine hydrochloride is weighed and dissolved in 65.0 mL of deionized water. The resulting solution is then added dropwise to 35.18 g of a 25 wt% N,N,N-trimethyl-1-adamantyl ammonium hydroxide solution under stirring, and stirred evenly to obtain solution A; 33.33 g of the above-mentioned silica sol is added to solution A. During the addition process, attention should be paid to adjusting the stirring speed. When a colloidal substance is found in the experiment, the stirring speed should be increased accordingly. When the solution forms a sol, the stirring speed is reduced; then, the silica sol container is washed with 40.0 mL of deionized water, and the washing liquid is also added to solution A. After stirring evenly, the pH of the solution is adjusted to between 11.2 and 11.5 with 0.1 M NaOH; then, stirring is continued at room temperature for 1.0 h to obtain a mixed solution B, that is, the preparation of the molecular sieve mother solution is completed;

[0092] Subsequently, 16.0 g of the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 1 were added to the molecular sieve mother liquor, and stirring was continued for 1 hour. The resulting mixture was then transferred to a PTFE-lined reactor and crystallized at a constant temperature of 150 ° C for 10 days. After the crystallization, the resulting crystallized product was centrifuged and washed multiple times to obtain a nano-micro superstructure acoustic material, which was then dried overnight at a temperature of 100 ° C and then calcined at a high temperature of 500 ° C for 6 hours to obtain a nano-micro superstructure acoustic material with a nano-micro superstructure, i.e., the acoustic enhancement material. According to the mass change of the material before and after crystallization, the mass ratio of the crystallized molecular sieve, i.e., MCM-35 zeolite molecular sieve, to the halloysite fiber-reinforced silica aerogel microspheres is 4.81:8.

[0093] Characterization Test Example 1

[0094] In this characterization test example, the halloysite fiber reinforced silica aerogel microspheres prepared in Preparation Example 1, the acoustic enhancement material prepared in Example 1 and the acoustic enhancement material prepared in Comparative Example 1 were analyzed by scanning electron microscopy. The experimental results are shown in Figure 2. Figure 1-Figure 3 As shown. Among them, Figure 1 This is a scanning electron microscope image of the halloysite fiber reinforced silica aerogel microspheres prepared in Preparation Example 1. Figure 1 It can be seen that after ball milling, the particles have a nearly spherical appearance and a particle size of about 300 μm; Figure 2 This is a scanning electron microscope image of the acoustic enhancement material prepared in Example 1. When preparing this material, halloysite fiber-reinforced silica aerogel microspheres are used as a carrier, and SSZ-13 zeolite molecular sieve is crystallized on the inner and outer surfaces of the carrier. After crystallization, the surface of the halloysite fiber-reinforced silica aerogel particles becomes somewhat rough and the particle size increases. In the acoustic enhancement material of Comparative Example 1, no aerogel microspheres are introduced during the preparation process, and the resulting SSZ-13 molecular sieve particles are ellipsoidal and less than 5 μm in size. Figure 3 shown.

[0095] Characterization Test Example 2

[0096] This characterization test example investigated the pore size distribution of the acoustic enhancement material prepared in Example 1. The obtained micropore distribution diagram, mesopore distribution diagram and macropore distribution diagram are shown as follows: Figure 4-Figure 6 As shown. Figure 4 It can be seen from the figure that the acoustic enhancement material has micropores, the size of which is between 0.45-0.6nm, with 0.47nm being the most distributed. Figure 5 It can be seen from the figure that the acoustic enhancement material has mesopores, and the mesopore sizes are mostly distributed at 2.1nm, 2.6nm and 2.9nm; Figure 6It can be seen from the figure that the acoustic enhancement material also has macropores within 100 μm, but most of the macropores are within 50 μm.

[0097] Performance Test Example 1

[0098] In this example, the strength of the halloysite fiber-reinforced silica aerogel particles prepared in Preparation Examples 1 and 2, the acoustic enhancement materials prepared in Examples 1 and 2, the unreinforced silica aerogel microspheres prepared in Comparative Preparation Example 1, and the acoustic enhancement material provided in Comparative Example 2 were tested in accordance with the provisions of Standard T / CECA 78-2022 "Porous Sound-Absorbing Particles for Microspeakers". The strength test results are shown in Table 1 below.

[0099] Table 1

[0100]

[0101]

[0102] According to the strength test results shown in Table 1 above, compared with the unreinforced (i.e., no reinforcing fibers are introduced) silica aerogel microspheres prepared in Comparative Preparation Example 1, the silica aerogel microspheres reinforced with halloysite fibers prepared in Preparation Example 1 have higher particle strength. Increasing the content of halloysite fibers will improve the particle strength of the silica aerogel microspheres to a certain extent. Specifically, the microspheres provided in Preparation Example 2 are silica aerogel microspheres reinforced with 10% wt of halloysite fibers, which also have correspondingly stronger particle strength than those in Comparative Preparation Example 1 and Preparation Example 1.

[0103] After the SSZ-13 zeolite molecular sieve is crystallized on the surface and inside of the halloysite fiber-reinforced silica aerogel microspheres, the particle strength of the final acoustic enhancement material will also be improved. Specifically, Examples 1 and 2 of the present invention prepare acoustic enhancement materials based on the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Examples 1 and 2, respectively. Compared with the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Examples 1 and 2, the particle strength of the acoustic enhancement materials provided in Examples 1 and 2 is improved, that is, after the SSZ-13 zeolite molecular sieve is crystallized on the surface and inside of the halloysite fiber-reinforced silica aerogel microspheres, the particle strength of the final acoustic enhancement material will be improved.

[0104] Comparative Example 2 prepared an acoustic enhancement material based on the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Example 1. Compared to Preparation Example 1, the particle strength of the acoustic enhancement material provided in Comparative Example 2 was also improved. This indicates that after the MCM-35 molecular sieve crystallizes on the surface and inside the halloysite fiber-reinforced silica aerogel microspheres, it also improves the particle strength of the resulting acoustic enhancement material. Compared with the acoustic enhancement materials provided in Examples 1 and 2 of the present invention, the particle strength of the acoustic enhancement material obtained by introducing the MCM-35 molecular sieve in Comparative Example 2 was not significantly different.

[0105] Performance Test Example 2

[0106] In this example, the water absorption rates of the halloysite fiber-reinforced silica aerogel particles prepared in Preparation Examples 1 and 2, the acoustic enhancement materials prepared in Examples 1 and 2, the unreinforced silica aerogel microspheres prepared in Comparative Preparation Example 1, and the acoustic enhancement materials prepared in Comparative Examples 1 and 2 were tested in accordance with the provisions of the standard T / CECA 78-2022 "Porous Sound-Absorbing Particles for Microspeakers". The water absorption test results are shown in Table 2 below.

[0107] Table 2

[0108] M1 / g M2 / g Water absorption / % Preparation Example 1 2.001 2.018 0.85 Preparation Example 2 2.001 2.037 1.80 Comparative Preparation Example 1 2.001 2.017 0.80 Example 1 2.002 2.011 0.45 Example 2 2.000 2.019 0.95 Comparative Example 1 2.002 2.010 0.40 Comparative Example 2 2.001 2.010 0.45

[0109] According to the water absorption test results shown in Table 2 above, the silica aerogel microspheres reinforced with an appropriate amount of halloysite fibers (Preparation Example 1), the unreinforced silica aerogel microspheres (Comparative Preparation Example 1), and the silica aerogel microspheres reinforced with an excess of halloysite fibers (Preparation Example 2) all have high water absorption. This is mainly because the presence of silanol groups in the silica aerogel gives it a high water absorption rate. At the same time, halloysite is a material with a low silicon-aluminum ratio and is also a material with a good affinity for water. Therefore, the excessive introduction of halloysite will lead to a significant increase in the overall water absorption of the material.

[0110] Since the acoustic enhancement materials provided in Examples 1 and 2 include halloysite fiber-reinforced silica aerogel microspheres and SSZ-13 zeolite molecular sieves, the SSZ-13 zeolite molecular sieves are chemically bonded to the interior and surface of the halloysite fiber-reinforced silica aerogel microspheres, and the SSZ-13 zeolite molecular sieves have excellent hydrophobicity, the water absorption rate of the acoustic enhancement materials provided in Examples 1 and 2 is lower than that of the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Examples 1 and 2, respectively.

[0111] Comparing the water absorption data of the acoustic enhancement materials provided in Examples 1 and 2, it can be seen that due to the higher water absorption of the silica aerogel microspheres reinforced with excess halloysite fibers provided in Preparation Example 2, the water absorption of the acoustic enhancement material provided in Example 2 is also significantly higher than that of the acoustic enhancement material provided in Example 1. Comparative Example 2, based on Preparation Example 1, introduces pure silica MCM-35 molecular sieve to prepare an acoustic enhancement material. Due to the excellent hydrophobicity of pure silica MCM-35 molecular sieve, the acoustic enhancement material provided in Comparative Example 2 has a water absorption very similar to that of the acoustic enhancement material provided in Example 1.

[0112] Performance Test Example 3

[0113] In this embodiment, the halloysite fiber reinforced silica aerogel microspheres prepared in Preparation Example 1-Preparation Example 2, the acoustic enhancement materials prepared in Example 1-Example 2, the unreinforced silica aerogel microspheres prepared in Comparative Example 1 and the acoustic enhancement materials prepared in Comparative Example 1-Comparative Example 2 were respectively filled into a standard sound cavity (the volume of the sound cavity was 1.0 cubic centimeters, the specific structure of the sound cavity can be referred to CN215072984U, and the filling amount of the sound-absorbing material to be tested was 300 mg), and then the acoustic performance tests were performed on them respectively, wherein the acoustic performance The test is carried out using conventional methods in the art. For example, the acoustic performance of each sample to be tested can be tested separately according to the "Measurement of Electrical Impedance" method shown in paragraphs 0049-0054 of Chinese patent application CN105049997A. Specifically, each sample to be tested is tested separately according to the "Measurement of Electrical Impedance" method to obtain an electrical impedance spectrum. The curve in the electrical impedance spectrum corresponds to the electrical impedance curve, wherein the frequency corresponding to the highest point of the electrical impedance curve is F0. When the speaker is not loaded with each sample to be tested, the measured F0 is marked as F 0-空腔 When the speaker is loaded with each sample to be tested, the measured F0 is marked as F 0-待测样品 , then the calculation formula of ΔF0 is:

[0114] ΔF0=F 0-空腔 -F 0-待测样品 .

[0115] The test signal used in the acoustic performance test process is the analog program signal or pink noise signal specified in GB / T 12060.1.

[0116] The test results obtained in this embodiment are shown in Table 3.

[0117] Table 3

[0118]

[0119] According to the acoustic performance test results shown in Table 3 above, the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 1 can achieve a certain low-frequency acoustic improvement effect. Compared with the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Example 1, when the comparative preparation example 1 does not introduce halloysite fiber as a reinforcing filler, the low-frequency acoustic improvement effect of the silica aerogel microspheres is not improved. Preparation Example 2 introduces an excessive amount of halloysite fiber reinforcing filler, and the low-frequency acoustic improvement effect of the halloysite fiber-reinforced silica aerogel microspheres obtained therefrom is slightly lower than that of Preparation Example 1 and Comparative Preparation Example 1.

[0120] Compared to the halloysite fiber-reinforced silica aerogel microspheres prepared in Preparation Examples 1 and 2 and the silica aerogel microspheres prepared in Comparative Preparation Example 1, the acoustic enhancement material prepared using molecular sieve powder alone in Comparative Example 1 exhibits improved low-frequency acoustic improvement. Comparative Example 2, based on the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Example 1, introduces MCM-35 molecular sieves via a template method to prepare an acoustic enhancement material. Compared to the halloysite fiber-reinforced silica aerogel microspheres provided in Preparation Example 1, the acoustic enhancement material provided in Comparative Example 2 also exhibits improved low-frequency acoustic improvement. However, compared to SSZ-13 zeolite molecular sieve (which is a molecular sieve with a three-dimensional 8-membered ring pore structure), MCM-35 molecular sieve is a molecular sieve with a one-dimensional 8-membered ring pore structure, and its porosity, accessible volume, specific surface area, etc. are all lower. After crystallization on the surface and inside of the halloysite fiber-reinforced silica aerogel microspheres, the improvement effect on the porosity, accessible volume, and specific surface area of ​​the final acoustic enhancement material is limited. Therefore, the acoustic enhancement material provided in Comparative Example 2 has limited improvement on the low-frequency acoustic effect. Specifically, the low-frequency acoustic improvement effect of the acoustic enhancement material provided in Comparative Example 2 is significantly worse than that of the acoustic enhancement material provided in Example 1.

[0121] Compared to the acoustic enhancement materials prepared in Comparative Examples 1 and 2, in Examples 1 and 2 of the present invention, the molecular sieve mother liquor crystallizes on the surface and interior of the halloysite fiber-reinforced silica aerogel microspheres to obtain a nano-micro-metastructure material having micropores, mesopores, and macropores, so that the acoustic enhancement materials prepared therefrom have excellent low-frequency acoustic improvement effects. However, Example 2 uses an excess of halloysite fiber-reinforced silica aerogel microspheres to prepare a nano-micro-superstructure acoustic enhancement material. Compared to Example 1, the low-frequency acoustic improvement effect of the nano-micro-superstructure acoustic enhancement material provided by Example 2 is reduced, indicating that the introduction of excess halloysite fiber-reinforced filler slightly reduces the low-frequency acoustic improvement effect of the resulting nano-micro-superstructure acoustic enhancement material.

[0122] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, substitutions of equivalent components, or equivalent changes and modifications made within the scope of patent protection, should still fall within the scope of this patent. Furthermore, the technical features of this invention may be freely combined with one another, with other technical inventions, and with other technical inventions.

Claims

1. An acoustic enhancement material, characterized in that: The acoustic enhancement material has micropores, mesopores and macropores, and includes silica aerogel reinforced with a fibrous structure reinforcing filler and SSZ-13 zeolite molecular sieve, wherein the SSZ-13 zeolite molecular sieve is chemically bonded to the interior and surface of the silica aerogel reinforced with the fibrous structure reinforcing filler.

2. The acoustic enhancement material according to claim 1, characterized in that The mass ratio of the SSZ-13 zeolite molecular sieve to the silica aerogel reinforced with the fibrous structure reinforcing filler is 1:1-1:

4.

3. The acoustic enhancement material according to claim 1 or 2, characterized in that: The SSZ-13 zeolite molecular sieve includes a pure silicon structure molecular sieve, a silicon-aluminum structure molecular sieve, a silicon-phosphorus-aluminum structure molecular sieve or a phosphorus-aluminum structure molecular sieve.

4. The acoustic enhancement material according to claim 1, characterized in that Taking the total weight of SiO2 in the silica aerogel reinforced with the fibrous structure reinforcing filler as 100%, the content of the fibrous structure reinforcing filler is 1-8%.

5. The acoustic enhancement material according to claim 1 or 4, characterized in that: The silica aerogel reinforced with a fibrous structure reinforcing filler comprises a fibrous structure reinforcing filler and silica aerogel, and the fibrous structure reinforcing filler is uniformly dispersed in the silica aerogel.

6. The acoustic enhancement material according to claim 1 or 4, characterized in that: The size of the silica aerogel reinforced with the fibrous structure reinforcing filler is 35-50 meshes.

7. The acoustic enhancement material according to claim 1 or 2, characterized in that: The fibrous structure reinforcing filler includes one or a combination of halloysite, boehmite, mullite and asbestos.

8. The method for preparing the acoustic enhancement material according to any one of claims 1 to 7, characterized in that: The preparation method comprises: According to the structure of SSZ-13 zeolite molecular sieve, a framework element source is selected and the framework element source, an alkali source, a mineralizer and a template agent are dissolved in deionized water to obtain a molecular sieve mother liquor; The silica aerogel reinforced with a fibrous structure reinforcing filler is added to the molecular sieve mother solution and mixed evenly, the obtained mixed solution is crystallized, and finally the crystallized product is washed, dried and calcined to obtain the acoustic enhancement material.

9. The preparation method according to claim 8, characterized in that The preparation method of the silica aerogel reinforced with the fibrous structure reinforcing filler comprises: A silicon source, a cosolvent and deionized water are mixed to obtain a first mixed liquid, an acidic catalyst is added to the first mixed liquid to hydrolyze the silicon source to produce a sol, a gel accelerator and a fibrous structure reinforcing filler are then added to the sol and mixed evenly to obtain a second mixed liquid, an alkaline catalyst is then added to the second mixed liquid to form a wet gel, and finally the wet gel is aged and dried to obtain the silica aerogel reinforced with the fibrous structure reinforcing filler.

10. The preparation method according to claim 9, characterized in that The silicon source is organic silicon and / or inorganic silicon, wherein the organic silicon includes one or a combination of ethyl orthosilicate, methyl orthosilicate, polysiloxane, methyltrimethoxysilane, methyltriethoxysilane and silsesquioxane, and the inorganic silicon includes one or a combination of silica sol, water glass, sodium silicate and silicon tetrachloride.

11. The preparation method according to claim 8, characterized in that The crystallization temperature is 60-200° C., and the crystallization time is 1 day to 10 days.

12. A loudspeaker comprising one or more sound-emitting units and one or more housings, wherein the one or more sound-emitting units and the one or more housings are combined to form a rear cavity of the loudspeaker, characterized in that: At least one of the speaker front cavity, the speaker rear cavity, the shell and the sound-emitting unit is equipped with the acoustic enhancement material according to any one of claims 1 to 7.

13. The loudspeaker according to claim 12, wherein: The speaker is a micro speaker.

14. An electronic device, characterized in that: The electronic device includes the speaker according to claim 12 or 13.

15. The electronic device according to claim 14, characterized in that The electronic devices include smartphones, TWS earphones, headphones, smart glasses, smart watches, VR devices, AR devices, tablets or thin and light laptops.

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