Sound-absorbing and energy-storing multifunctional particles as well as preparation method and application thereof

Abstract

The invention discloses a multifunctional sound-absorbing and energy-storing particle and a preparation method and application thereof, according to the preparation method, a light porous material is used as a carrier, a phase change material is adsorbed by adopting an impregnation method, and through double-layer packaging of composite functional powder and a slurry curing layer, the technical bottleneck that leakage is easy to occur in traditional single packaging is broken through. In the multifunctional particle, the inner core adsorbs the phase change material, the functional packaging layer is added with the sound absorption functional powder while ensuring seepage prevention, and the slurry packaging layer provides mechanical support and also provides sound absorption. The preparation method is simple, environment-friendly, low in economic cost and good in curing effect, and the multifunctional particles have multiple functions of sound absorption, energy storage and the like, can be applied to a bearing structure material, effectively solve the key technical problems that a phase change material is prone to leakage, insufficient in mechanical property, poor in thermal stability and the like, expand the application boundary of the phase change material and have wide application prospects. The invention provides an innovative solution for the fields of building energy conservation and high-performance concrete, and has important theoretical value and wide engineering application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional materials, and in particular relates to a sound-absorbing and energy-storing multifunctional particle and a preparation method and application thereof. Background Art

[0002] With the advancement of green building concepts, modern architecture places higher demands on the comprehensive performance of materials. Traditional building material systems suffer from a significant functional fragmentation: while porous sound-absorbing materials such as expanded perlite and mineral wool have excellent acoustic attenuation properties (sound absorption coefficients exceeding 0.8), they have poor thermal inertia and lack temperature regulation capabilities. Phase-change energy storage materials such as paraffin wax and expanded graphite, while possessing significant thermal enthalpy values ​​(typically >150 J / g), have sound absorption coefficients below 0.3 due to their dense structure, making them difficult to meet acoustic environment control requirements. This functional simplification often requires multi-layer composite structures for building envelopes, increasing construction complexity (interlayer interface issues lead to a 15% to 20% performance degradation) and increasing the amount of building materials used (statistically, wall thickness increases by approximately 30%).

[0003] In recent years, researchers have attempted to overcome technical bottlenecks through functional composites, but existing composite systems generally suffer from environmental adaptability deficiencies: when humidity exceeds 70% RH, porous matrices are prone to capillary condensation (resulting in a 30%-50% loss in sound absorption performance), while temperature cycling-induced migration of phase-change components can lead to a 12%-15% decrease in energy storage efficiency. This underlying technical contradiction manifests itself in two aspects: First, there is an inherent conflict between the structural requirements for sound absorption and energy storage—the former relies on open, interconnected pores (porosity > 60%), while the latter requires sealed microcavities to prevent leakage of the phase-change medium. Second, traditional composite processes struggle to achieve precise spatial distribution of functional components. This results in the comprehensive performance index (sound absorption coefficient × phase change enthalpy / cost) of existing materials generally being below 40, significantly short of the engineering practical threshold (>80). Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a sound-absorbing and energy-storing multifunctional particle, as well as a preparation method and application thereof. The multifunctional particle not only has good sound absorption performance, but can also achieve temperature regulation through phase change energy storage. It can be used to prepare temperature-controlled mortar or concrete, enhancing its thermal regulation and energy storage capabilities; at the same time, it can also be used to manufacture sound-absorbing panels and other acoustic materials to effectively reduce noise pollution and improve the acoustic performance of the environment inside and outside the building. It is widely used in the fields of construction, decoration, engineering and environmental protection.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for preparing sound-absorbing and energy-storing multifunctional particles comprises the following steps:

[0007] Step 1) Preparation of the core: Mixing the porous particles with the molten phase change material and impregnating them at room temperature, under pressure or by vacuum adsorption to form the energy storage core;

[0008] Alternatively, the porous powder material is mixed with the molten phase change material, impregnated at room temperature, under pressure or vacuum adsorption, and finally granulated by extrusion to form the energy storage core;

[0009] Step 2) Preparation of a functional encapsulation layer: a porous powder material and metal micropowder are compounded to form a functional powder, and the energy storage core prepared in step 1) is then mixed with the functional powder and rolled onto the surface of the energy storage core to form a functional encapsulation layer;

[0010] Step 3) Preparation of slurry encapsulation layer: immerse the energy storage core particles treated in step 2) in slurry or use shelling and powder coating technology, and after natural curing, form a slurry encapsulation layer on the surface of the functional encapsulation layer.

[0011] Preferably, the phase change material in step 1) is at least one of paraffin, fatty acid, alcohol or inorganic hydrated salt; the phase change temperature of the phase change material is 20-80° C., and the phase change enthalpy value is ≥120 kJ / kg.

[0012] Preferably, the porous particles in step 1) are at least one of expanded perlite particles, foam aluminum particles, foam ceramic particles, and sponge particles; the porous particles have a diameter of 2 to 4 mm, an internal pore size of 10 to 50 μm, and a porosity of 75% to 95%.

[0013] Preferably, the porous powder material in step 1) and step 2) is at least one of porous silica, hollow porous carbon nanopowder, bentonite, wood powder, zeolite powder or expanded graphite powder; the specific surface area of ​​the porous powder material is ≥10m 2 / g.

[0014] Preferably, in step 1), the impregnation temperature is 35-90°C, the pressure is 0.09-0.15 MPa, and the time is 15-720 min; the mass ratio of the porous particles to the molten phase change material is 1:3-1:4; the mass ratio of the porous powder material to the molten phase change material is 1:3-1:4; and the diameter of the energy storage core is 2-4 mm.

[0015] Preferably, the metal powder in step 2) is at least one of steel slag powder, aluminum powder, and iron oxide powder; the specific surface area of ​​the metal powder is 300 to 800 m 2 / kg, metal element content ≥30%.

[0016] Preferably, in the functional powder in step 2), the mass ratio of porous powder material to metal micropowder is 5:1 to 20:1; the mass ratio of the energy storage core to the functional powder is (5 to 8): (1 to 3); and the thickness of the functional encapsulation layer is 0.5 to 1.0 mm.

[0017] Preferably, in step 3), the slurry is composed of grouting material, the grouting material contains 0-20% of clean fine sand with a particle size of less than 0.15 mm, the water-cement ratio is 0.10-0.30, the mortar fluidity of the slurry is 260-380 mm, and the compressive strength is ≥60 MPa; the curing time is 15-24 h.

[0018] The sound-absorbing and energy-storing multifunctional particles prepared by the above preparation method have a cylinder pressure strength of ≥4.5MPa, a sound absorption coefficient of ≥0.4, a phase change enthalpy value of ≥100kJ / kg, and a mass loss rate of <5% after 200 thermal cycles.

[0019] The application of the above-mentioned sound-absorbing and energy-storing multifunctional particles in temperature-controlled mortar, concrete or sound-absorbing panels.

[0020] The principles of the present invention are as follows:

[0021] The preparation process of the sound-absorbing and energy-storing multifunctional particles of the present invention is based on the wave-inducing effect of metal micropowders and a double-layer sealing design, combining the advantages of a functional packaging layer and a high-strength shell to achieve the multiple functionalities of the particles, including sound absorption, energy storage, and mechanical enhancement.

[0022] First, the metal micropowder acts as a waveguide within the functional encapsulation layer. Through its unique physical properties, the metal micropowder effectively guides the propagation of sound waves, generating a significant absorption effect as they pass through the particles. This effect enhances the particles' sound absorption, resulting in excellent noise reduction in acoustic environments. The metal micropowder's high surface area and strong sound absorption capacity further enhance the particles' sound attenuation.

[0023] Secondly, the particle's double-layer encapsulation design further enhances its overall performance. During the core preparation process, the energy storage material regulates temperature by absorbing or releasing heat, while the outer functional encapsulation layer and slurry encapsulation layer provide the necessary structural protection, ensuring the particle's stability and durability during use. This double-layer encapsulation not only effectively prevents leakage of the energy storage material but also enhances the particle's mechanical strength.

[0024] Finally, the shell is constructed from a high-strength sand-containing material, giving the pellets enhanced mechanical properties. This high-strength shell enhances the pellets' resistance to pressure and impact, resulting in excellent mechanical stability in practical applications. This design increases the pellets' load-bearing capacity and ensures they maintain good structural integrity over long-term use.

[0025] The beneficial effects of the present invention are as follows:

[0026] (1) Multifunctionality: The particles of the present invention possess multiple functions, including sound absorption, energy storage, and temperature regulation. The wave-inducing effect of the metal micropowder gives the particles excellent sound wave absorption capabilities, effectively reducing noise pollution; while the phase change energy storage material absorbs or releases heat when the temperature changes, regulating the ambient temperature and improving the comfort and energy efficiency of the building. This multifunctional design gives the particles unique advantages in a variety of application scenarios.

[0027] (2) High load capacity: The combination of a double-layer packaging structure and a dual-path core design enables the functional particles of the present invention to carry more energy storage materials, significantly improving energy storage density. Through the rational design of the core and packaging layer, the particles can not only effectively store thermal energy but also maintain high mechanical properties, making them suitable for high-load and high-intensity applications.

[0028] (3) Stability and cycle life: The present invention utilizes a double-layer packaging structure combining a bentonite adsorption layer with a cement encapsulation layer, effectively avoiding the leakage problem associated with traditional packaging. This double-layer packaging design not only enhances the structural stability of the particles but also improves their long-term reliability, enabling the particles to maintain a low mass loss rate (<5%) after 200 thermal cycles, demonstrating excellent durability and long-term stability.

[0029] (4) Simple process and environmental friendliness: The preparation process of the present invention is simple and easy to implement, capable of large-scale production, and fully utilizes waste resources such as steel slag powder, reducing the environmental burden. This process not only reduces production costs but also meets the requirements of sustainable development, promoting the application and promotion of green building materials. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below with reference to specific embodiments.

[0031] Unless otherwise specified, the technical means used in the following examples are all conventional means well known to those skilled in the art, and experimental methods without specific conditions are all conventional methods in the art.

[0032] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0033] A method for preparing sound-absorbing and energy-storing multifunctional particles, comprising the following specific steps:

[0034] (1) Preparation of the core

[0035] Scheme (1-1): The porous particles are mixed with the molten phase change material in a mass ratio of 1:3 to 1:4, and impregnated at room temperature, pressurized or vacuum adsorption. The impregnation is carried out for 15 to 720 minutes at a temperature of 35 to 90°C and a pressure of 0.09 to 0.15 MPa to form an energy storage core.

[0036] Scheme (1-2): The porous powder material and the molten phase change material are mixed in a mass ratio of 1:3 to 1:4, and impregnated at room temperature, pressurized or vacuum adsorption. The impregnation is carried out at a temperature of 35 to 90°C and a pressure of 0.09 to 0.15 MPa for 15 to 720 minutes. Finally, the energy storage core (with a diameter of 2 to 4 mm) is formed by extrusion granulation.

[0037] The phase change material is at least one of paraffin, fatty acid, alcohol or inorganic hydrated salt, and has a relatively ideal phase change temperature (20-80° C.) and phase change enthalpy value (≥120 kJ / kg).

[0038] The porous particles are at least one of expanded perlite particles, foam aluminum particles, foam ceramic particles, and sponge particles; the porous particles have a diameter of 2 to 4 mm, an internal pore size of 10 to 50 μm, and a porosity of 75% to 95%.

[0039] The porous powder material is at least one of porous silica, hollow porous carbon nanopowder, bentonite, wood powder, zeolite powder or expanded graphite powder; the specific surface area of ​​the porous powder material is ≥10m 2 / g.

[0040] (2) Preparation of functional encapsulation layer

[0041] The porous powder material and metal micropowder are compounded in a mass ratio of 5:1 to 20:1 to form a functional powder, and then the energy storage core prepared above is mixed with the functional powder in a mass ratio of (5 to 8): (1 to 3), and rolled by horizontal stirring or drum coating to form a primary encapsulation layer (functional encapsulation layer, thickness controlled at 0.5 to 1.0 mm) on the surface of the energy storage core.

[0042] The metal powder is at least one of steel slag powder, aluminum powder, and iron oxide powder, and has a large specific surface area (300-800m 2 / kg) and a higher metal element content (≥30%), which helps to improve the mechanical properties and thermal stability of the particles.

[0043] (3) Preparation of slurry encapsulation layer

[0044] The energy storage core particles treated as above are immersed in slurry (held in a wire mesh bag and rolled through a slurry pool) or coated with powder using a shell coating technique. After natural curing for 15 to 24 hours, an outer packaging structure (slurry packaging layer) is formed on the surface of the functional packaging layer to obtain the sound-absorbing and energy-storing multifunctional particles.

[0045] The slurry is composed of grouting material, which contains 0-20% of clean fine sand with a particle size of less than 0.15mm, a water-cement ratio of 0.10-0.30, a mortar fluidity controlled at 260-380mm, and has high compressive strength (≥60MPa).

[0046] Example 1

[0047] A method for preparing sound-absorbing and energy-storing multifunctional particles, comprising the following specific steps:

[0048] (1) Expanded perlite (particle size 2-4 mm, internal pore size 15-40 μm, porosity about 86%) was used as the core material and mixed with polyethylene glycol phase change material. The mass ratio of expanded perlite to polyethylene glycol was 1:4. The material was impregnated by pressurized adsorption at a temperature of 60 ° C and a pressure of 0.1 MPa for 60 min to ensure that the polyethylene glycol was fully adsorbed into the pores of the expanded perlite to form an energy storage core (diameter 2-4 mm).

[0049] (2) The resulting energy storage core is mixed with a bentonite + aluminum powder composite powder (the mass ratio of bentonite to aluminum powder is 10:1) at a mass ratio of 5:1, and a functional encapsulation layer (thickness 0.5-0.7 mm) is formed by rolling coating. This process can effectively and evenly coat the bentonite / aluminum powder composite powder on the surface of the energy storage core, providing a certain degree of isolation.

[0050] (3) The treated energy storage core particles were immersed in a pure grouting material composed of P·II 52.5 cement, with a water-cement ratio of 0.15 and a mortar fluidity of 315 mm. The grouting material was cured for 24 hours to form an outer cement encapsulation structure, thereby producing the sound-absorbing and energy-storing multifunctional particles. This cement encapsulation not only enhances the mechanical strength of the particles but also acts as a leak-proof material, ensuring that the phase change material does not leak during use.

[0051] Example 2

[0052] A method for preparing sound-absorbing and energy-storing multifunctional particles, comprising the following specific steps:

[0053] (1) The porous silica powder + zeolite powder composite powder (the mass ratio of porous silica powder to zeolite powder is 1:1, and the specific surface area of ​​the composite powder is 17.9m 2 / g) as the core material, mixed with a fatty acid phase change material, the mass ratio of the composite powder to the fatty acid phase change material being 1:3, and impregnation was performed using a pressurized adsorption method at a temperature of 85°C and a pressure of 0.12 MPa for 90 minutes to ensure that the fatty acid phase change material fully penetrated into the porous silica powder / zeolite powder composite powder. Finally, extrusion granulation was performed to form an energy storage core (diameter 2-4 mm).

[0054] (2) The obtained energy storage core was mixed with a wood powder + iron oxide powder composite powder (the mass ratio of wood powder to iron oxide powder was 10:3) at a mass ratio of 7:2, and a functional encapsulation layer (thickness 0.6-0.8 mm) was formed by rolling coating. This encapsulation structure can provide better protection and prevent leakage of the energy storage material.

[0055] (3) The treated energy storage core particles were immersed in a grouting material consisting of grouting powder and 10% fine sand, with a water-cement ratio of 0.1 and a mortar fluidity of 280 mm. The grouting material was cured for 18 hours to form an outer cement encapsulation structure, thereby producing the sound-absorbing and energy-storing multifunctional particles. This outer cement encapsulation effectively enhances the mechanical strength of the particles and further prevents leakage of the phase change material.

[0056] Example 3

[0057] A method for preparing sound-absorbing and energy-storing multifunctional particles, comprising the following specific steps:

[0058] (1) Hollow porous carbon nanopowder + bentonite + wood powder composite powder (the mass ratio of hollow porous carbon nanopowder, bentonite and wood powder is 3:5:2, and the specific surface area of ​​the composite powder is 27.1m 2 / g) as the core material, mixed with paraffin phase change material, the mass ratio of composite powder to paraffin is 1:3.6, and impregnation is carried out by pressurized adsorption method. At a temperature of 75°C and a pressure of 0.15MPa, the impregnation is carried out for 80min to ensure that the paraffin can be fully adsorbed into the hollow porous carbon nanometer powder + bentonite + wood powder composite powder. Finally, it is extruded and granulated to form an energy storage core (diameter 2-4mm).

[0059] (2) The resulting energy storage core was mixed with a composite powder of zeolite powder and steel slag powder (the mass ratio of zeolite powder to steel slag powder was 13:2) at a mass ratio of 6:1, and a functional encapsulation layer (thickness 0.5-0.8 mm) was formed by rolling coating. This layer of encapsulation can effectively prevent leakage of the phase change material and increase the stability of the particles.

[0060] (3) The treated energy storage core particles were immersed in a cement slurry consisting of sulfoaluminate cement, silica fume, and cellulose ether with a water-cement ratio of 0.20 and a mortar fluidity of 275 mm. The slurry was cured for 20 hours to form an outer cement encapsulation structure, thereby producing the sound-absorbing and energy-storing multifunctional particles. This encapsulation not only enhanced the mechanical strength of the particles but also effectively prevented leakage of the phase change material.

[0061] Example 4

[0062] A method for preparing sound-absorbing and energy-storing multifunctional particles, comprising the following specific steps:

[0063] (1) Expanded graphite (particle size 2-4 mm, internal pore size 10-35 μm, porosity about 76%) was used as the core material and mixed with polyethylene glycol phase change material. The mass ratio of expanded graphite to polyethylene glycol was 1:3.2. The mixture was impregnated by pressurized adsorption at a temperature of 50 ° C and a pressure of 0.11 MPa for 60 min to ensure that the polyethylene glycol was fully adsorbed into the pores of the expanded graphite to form an energy storage core (diameter 2-4 mm).

[0064] (2) The resulting energy storage core was mixed with a composite powder of bentonite, wood powder, and aluminum powder (the mass ratio of bentonite, wood powder, and aluminum powder was 6:3:1) at a mass ratio of 8:3, and a functional encapsulation layer (thickness 0.5-0.9 mm) was formed by rolling coating. This process can effectively and evenly wrap the composite powder on the surface of the phase change core, providing a certain degree of isolation.

[0065] (3) The treated energy storage core particles were immersed in a cement slurry consisting of P·II 52.5 cement, fly ash, and 15% fine sand, with a water-cement ratio of 0.18 and a mortar fluidity of 260 mm. The slurry was cured for 24 hours to form an outer cement encapsulation structure, thereby producing the sound-absorbing and energy-storing multifunctional particles. This cement encapsulation not only enhances the mechanical strength of the particles but also acts as a leak-proof material, ensuring that the phase change material does not leak during use.

[0066] Comparative Example 1

[0067] (1) Expanded perlite (particle size 2-4 mm, internal pore size 15-40 μm, porosity about 86%) was used as the core material and mixed with polyethylene glycol phase change material. The mass ratio of expanded perlite to polyethylene glycol was 1:4. The material was impregnated by pressurized adsorption at a temperature of 60 ° C and a pressure of 0.1 MPa for 60 min to form an energy storage core (diameter 2-4 mm).

[0068] (2) The energy storage core particles are immersed in pure grouting material, which is composed of P·II 52.5 cement, with a water-cement ratio of 0.15 and a mortar fluidity of 315 mm. The grouting material is cured for 24 hours to form a single-layer package. This packaging method is relatively simple, but its sealing and stability are relatively poor.

[0069] Test Example 1

[0070] The products prepared in Examples 1-4 and Comparative Example 1 were subjected to performance tests, as follows:

[0071] The phase change enthalpy value was tested using a differential scanning calorimeter with a test range of 5°C to 75°C, a temperature accuracy of ±0.05°C, a temperature precision of ±0.008°C, and a sensitivity of 0.18mW.

[0072] The mass loss rate after 200 thermal cycles is tested in a temperature box, with the low temperature controlled at -25°C to -5°C, the high temperature controlled at 55°C to 75°C, and the cycle time controlled at 5 to 15 minutes.

[0073] The cylinder pressure strength test is carried out according to the standard GB / T 17431-2010 "Light aggregate and its test methods", and the pressure bearing area is F = 10000mm 2 , use a uniform load at a speed of 300 to 500N per second, and record the pressure value when the punching die is pressed into the depth of 20mm.

[0074] The sound absorption coefficient test is based on GB / T 18696.2-2002 "Measurement of sound absorption coefficient and impedance in acoustic impedance tubes Part 2: Transfer function method". The test mold filled with aggregate is fixed vertically to the front end of the standing wave tube, and the sound absorption coefficient is calculated using the transfer function method.

[0075] The test results are shown in Table 1 below.

[0076] Table 1 Performance test results

[0077] Group Phase change enthalpy (kJ / kg) Mass loss rate (%) Cylinder pressure strength (MPa) Sound absorption coefficient Example 1 119.2 ＜1 5.2 0.41 Example 2 175.5 1.7 4.7 0.52 Example 3 157.9 1.2 4.5 0.60 Example 4 108.7 ＜1 5.1 0.57 Comparative Example 1 89.7 3.8 3.0 0.10

[0078] In performance testing, Examples 1-4 and Comparative Example 1 demonstrate the effects of different core materials, phase change materials, and packaging structures on the performance of high-enthalpy phase change particles. Comparative analysis of the data in Table 1 clearly demonstrates that the double-layer packaging process (Examples 1-4) demonstrates superiority in all performance aspects, as detailed below:

[0079] (1) In terms of phase change enthalpy, Example 2 (combination of porous silica powder + zeolite powder and fatty acid phase change material) achieved the highest phase change enthalpy (175.5 kJ / kg), indicating that this combination has a higher energy storage capacity. In contrast, Comparative Example 1 (single-layer encapsulation of expanded perlite and polyethylene glycol) performed poorly in terms of energy storage, with an enthalpy of only 89.7 kJ / kg, demonstrating the shortcomings of the single-layer encapsulation structure.

[0080] (2) In terms of leakage rate, the double-layer packaging processes of Examples 1-4 all exhibited low mass loss rates (<2%), while the single-layer packaging of Comparative Example 1 exhibited a mass loss rate of 3.8%, significantly higher than the double-layer packaging process. This result demonstrates that the double-layer packaging process has significant advantages in preventing phase change material leakage, particularly in applications requiring long-term stability, where double-layer packaging is more reliable.

[0081] (3) In terms of mechanical strength, Example 1 (a combination of expanded perlite and polyethylene glycol) exhibited the highest cylinder compressive strength (5.2 MPa), indicating that its double-layer packaging structure provided high mechanical stability. In contrast, the cylinder compressive strength of Comparative Example 1 was only 3.0 MPa, demonstrating the structural strength deficiency of single-layer packaging.

[0082] (4) In terms of sound absorption, Example 3 (hollow porous carbon nanopowder + bentonite + wood powder and paraffin phase change material) exhibited the best sound absorption coefficient (0.60), effectively improving the acoustic performance of the particles. Other examples incorporating metal powder into the functional encapsulation layer also exhibited certain sound absorption properties, while the sound absorption coefficient of Comparative Example 1 was only 0.10, demonstrating the acoustical disadvantages of the single-layer encapsulation process.

[0083] In summary, the double-layer encapsulation process of the present invention demonstrates significant advantages in thermal stability, leakage rate control, mechanical strength, and sound absorption, making it particularly suitable for applications requiring long-term stable performance, such as building energy conservation, temperature control, and energy storage. Conventional single-layer encapsulation processes, on the other hand, suffer from low phase change enthalpy, poor thermal stability, high leakage rate, insufficient mechanical strength, and poor sound absorption, limiting their suitability for long-term use. Therefore, the double-layer encapsulation process of the present invention is more suitable for preparing granular materials with sound absorption, energy storage, and multiple functions.

[0084] The embodiments described above are only some of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but merely represents selected embodiments of the present invention. The scope of protection of the present invention shall be based on the scope required by the claims. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing sound-absorbing and energy-storing multifunctional particles, characterized in that: The following steps are involved: Step 1) Preparation of the core: Mixing the porous particles with the molten phase change material and impregnating them at room temperature, under pressure or by vacuum adsorption to form the energy storage core; Alternatively, the porous powder material is mixed with the molten phase change material, impregnated at room temperature, under pressure or vacuum adsorption, and finally granulated by extrusion to form the energy storage core; Step 2) Preparation of a functional encapsulation layer: a porous powder material and metal micropowder are compounded to form a functional powder, and the energy storage core prepared in step 1) is then mixed with the functional powder and rolled onto the surface of the energy storage core to form a functional encapsulation layer; Step 3) Preparation of slurry encapsulation layer: immerse the energy storage core particles treated in step 2) in slurry or use shelling and powder coating technology, and after natural curing, form a slurry encapsulation layer on the surface of the functional encapsulation layer.

2. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: Step 1) The phase change material is at least one of paraffin, fatty acid, alcohol or inorganic hydrated salt; the phase change temperature of the phase change material is 20-80° C., and the phase change enthalpy value is ≥120 kJ / kg.

3. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: In step 1), the porous particles are at least one of expanded perlite particles, foam aluminum particles, foam ceramic particles, and sponge particles; the porous particles have a diameter of 2 to 4 mm, an internal pore size of 10 to 50 μm, and a porosity of 75% to 95%.

4. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: The porous powder material in step 1) and step 2) is at least one of porous silica, hollow porous carbon nanopowder, bentonite, wood powder, zeolite powder or expanded graphite powder; the specific surface area of ​​the porous powder material is ≥10m 2 / g.

5. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: Step 1) The impregnation temperature is 35-90°C, the pressure is 0.09-0.15 MPa, and the time is 15-720 min; the mass ratio of the porous particles to the molten phase change material is 1:3-1:4; the mass ratio of the porous powder material to the molten phase change material is 1:3-1:4; and the diameter of the energy storage core is 2-4 mm.

6. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: Step 2) The metal powder is at least one of steel slag powder, aluminum powder, and iron oxide powder; the specific surface area of ​​the metal powder is 300 to 800 m 2 / kg, metal element content ≥30%.

7. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: In step 2), the mass ratio of the porous powder material to the metal micropowder is 5:1 to 20:1; the mass ratio of the energy storage core to the functional powder is (5 to 8): (1 to 3); and the thickness of the functional encapsulation layer is 0.5 to 1.0 mm.

8. The method for preparing sound-absorbing and energy-storing multifunctional particles according to claim 1, characterized in that: Step 3) The slurry is composed of a grouting material, the grouting material contains 0-20% of clean fine sand with a particle size of less than 0.15 mm, the water-cement ratio is 0.10-0.30, the mortar fluidity of the slurry is 260-380 mm, and the compressive strength is ≥60 MPa; the curing time is 15-24 hours.

9. The sound-absorbing and energy-storing multifunctional particles prepared by the preparation method according to any one of claims 1 to 8, characterized in that: The particles have a cylinder pressure strength of ≥4.5 MPa, a sound absorption coefficient of ≥0.4, a phase change enthalpy value of ≥100 kJ / kg, and a mass loss rate of <5% after 200 thermal cycles.

10. Use of the sound-absorbing and energy-storing multifunctional particles according to claim 9 in temperature-controlled mortar, concrete or sound-absorbing panels.