Thermal insulation and noise reduction foam and method of making same

Abstract

The application provides a heat-insulating and noise-reducing foam material and a preparation method thereof, and belongs to the technical field of organic polymers. The foam hole structure is mainly controlled by microwave frequency division foaming to have a high closed hole rate on the surface and a high open hole rate gradient distribution inside, a nucleating agent is added to control the size of foaming, and water-soluble particles are added, so that micron-level connected pores are formed after foaming by water washing, and the sound absorption performance is further optimized; finally, the surface is further treated by heat pressing to further improve the closed hole rate of the surface; so that the whole presents a foam structure of external high closed hole rate and internal high open hole rate for external heat insulation and internal noise reduction, and realizes the dual functions of heat insulation and noise reduction.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic polymers, and particularly relates to a heat-insulating and noise-reducing foam material and a preparation method thereof. BACKGROUND

[0002] Melamine foam is a high-performance thermosetting material with melamine-formaldehyde resin as a base material, which has a unique three-dimensional porous network structure and low thermal conductivity, and performs excellently in heat insulation and noise reduction.

[0003] In terms of heat insulation, the thermal conductivity of melamine foam is a core index for measuring heat insulation performance. The higher the closed cell rate, the less the air convection heat transfer, and the better the heat insulation effect. The temperature resistance range of melamine foam is wide, up to-180 DEG C to 240 DEG C, and it is widely used in building walls, industrial pipelines, air conditioning systems and spacecraft insulation layers, which significantly reduces heat loss and improves equipment operating efficiency.

[0004] In terms of noise reduction, the three-dimensional interconnected grid with high open porosity is the key to sound absorption. After the sound wave enters, it is converted into heat energy through grid vibration and viscous resistance. The sound absorption coefficient of medium and high frequency noise (above 250 Hz) can reach 0.9-0.95. The high open structure absorbs sound wave energy through friction and reflection, and is particularly good at controlling medium and high frequency noise. It is used for engine compartment sound insulation of vehicles, building acoustics engineering and industrial equipment noise reduction, which greatly improves the quality of sound environment. In addition, the material has the advantages of environmental protection, easy processing and aging resistance, and becomes a key technology material for energy saving and environmental protection and acoustic optimization.

[0005] It can be seen that the heat insulation capacity of melamine foam relies on high closed porosity, while noise reduction relies on high open porosity. There is a contradiction between the two main performances in structure. At present, the following solutions are available:

[0006] 1. Surface treatment: by attaching a heat insulation material (such as aluminum foil) on the surface of the melamine foam with high open porosity; and performing heat pressing treatment on the high open foam to form a dense closed cell layer on the surface after heat pressing.

[0007] 2. Mixed material modification: such as embedding silica aerogel (nano-porous structure) into melamine foam, using the ultra-low thermal conductivity of aerogel to compensate for the heat loss of open structure; or adding flexible chain segments such as toughening agents to reduce crosslinking density, so that the foam has both open-cell sound absorption and closed-cell heat insulation properties; and introducing flame retardants to improve flame retardancy while optimizing the distribution of pores by filling inorganic particles.

[0008] 3. Foaming process improvement: by adjusting the foaming process to form a closed-cell-open-cell transition layer from the outside to the inside in the foam;

[0009] 4. Compound: using high closed porosity melamine foam plate on the outer layer; and sandwiching high open porosity melamine foam plate in the inner layer to consider heat insulation and noise reduction.

[0010] But no matter which solution has its limitations and scope, so how to choose the right solution is the problem of preparing melamine resin foam with high insulation and high noise reduction. SUMMARY

[0011] The purpose of the present application is to solve the structural contradiction between the two main performances of melamine foam, namely insulation and noise reduction.

[0012] In order to achieve the above purpose, the present application provides a preparation method of insulation and noise reduction foam material, comprising the following steps:

[0013] S1 Preparation of prepolymer solution: take melamine, polyformaldehyde into the reaction kettle, adjust the pH to 10.5-11.5 with strong base; stirring and heating and adding polydiethylene glycol to carry out hydroxymethylation reaction; after the reaction is completed, the reaction is terminated by cooling, and the prepolymer solution is obtained;

[0014] The mass ratio of melamine, polyformaldehyde and polydiethylene glycol is 100:30-40:4-10;

[0015] S2 foaming synthesis: adding water-soluble particles, volatile foaming agent, calcium carbonate, silane, blocked isocyanate, emulsifier and formic acid into the prepolymer solution; stirring to form a foaming liquid;

[0016] The foaming liquid is first foamed by high-frequency microwave and then foamed by low-frequency, and the frequency difference between the two foaming is at least 1000MHz;

[0017] After foaming, high temperature curing is carried out to obtain a preliminary foaming resin;

[0018] The addition amount of water-soluble particles, volatile foaming agent, calcium carbonate, silane, isocyanate, emulsifier and formic acid is respectively:

[0019] Water-soluble particles: 20-50%

[0020] Volatile foaming agent: 5-15%

[0021] Calcium carbonate: 2-5%

[0022] Silane: 0.5-1.5%

[0023] Blocked isocyanate: 2-4%

[0024] Emulsifier: 2-5%

[0025] Formic acid: 0.5-2%

[0026] S3 post-treatment: the preliminary foaming resin is put into water to wash off the water-soluble particles; then dried, and then hot-pressed after spraying glue powder on the surface; insulation and noise reduction foam material is obtained.

[0027] Preferably, the molecular weight of the polyethylene glycol is ≤4000.

[0028] Preferably, the particle size of the calcium carbonate is ≤5μm.

[0029] Preferably, the emulsifier is an anionic surfactant.

[0030] Preferably, the blocked isocyanate is blocked isophorone diisocyanate, hexamethylene diisocyanate and / or dicyclohexylmethane diisocyanate.

[0031] Preferably, the water-soluble particles are inorganic salts or water-soluble polymers.

[0032] Preferably, the rubber powder is a thermoplastic polymer; the particle size is 20-100μm.

[0033] Preferably, in the preparation of the prepolymer solution of step S1, the reaction temperature of the hydroxymethylation reaction is 85-110℃, and the time is at least 120min.

[0034] Preferably, in the preparation of the foaming synthesis of step S2, the time of high-frequency microwave foaming is 60-90s; the time of low-frequency foaming is 120-180s; the temperature of high-temperature curing is 100-120℃, and the time of high-temperature curing is ≥1h.

[0035] Preferably, in the preparation of the post-processing of step S3, the addition amount of the rubber powder is at least 10% of the mass percentage of the prepolymer; the hot-pressing temperature is ≥120℃; and the holding time is at least 5min.

[0036] In the present application, melamine and paraformaldehyde: as the main reactants, undergo hydroxymethylation reaction under strong alkaline conditions to generate cross-linked melamine resin network, forming the material skeleton.

[0037] The addition of polyethylene glycol (PEG) can significantly reduce the viscosity of the resin system; the dispersion of PEG prevents particle aggregation and ensures uniform foaming process; the gas diffusion during foaming is more uniform, reducing the proportion of closed pores and forming a partially open structure.

[0038] And the hydroxyl groups in PEG partially react with the active groups (such as hydroxyl groups) in the resin, introducing flexible long-chain structures into the resin molecular chain, thereby achieving toughening effect.

[0039] Polyethylene glycol (PEG, molecular weight ≤4000): as a toughening agent and reaction medium, it combines with the resin molecular chain through ether bonds, increases the flexible chain segment, and improves the toughness of the foam.

[0040] The water-soluble particles act as sacrificial templates, and after foaming and water washing, they form interconnected pores, optimizing the sound absorption performance.

[0041] The foaming agent selects volatile foaming agents such as alkanes such as n-pentane, cyclopentane, etc.; the gas is generated by heating vaporization to form a uniform cell structure. Compared with azo compounds, a higher open porosity can be formed.

[0042] However, volatile foaming agents are prone to cause wide bubble size distribution, so calcium carbonate is added as a nucleating agent in the present application to reduce the bubble nucleation energy and refine the cells; small cells can force sound waves to reflect multiple times within the pores; and the compressive strength can also be improved.

[0043] It is traditionally believed that the nucleating agent is uniformly dispersed in the foaming liquid, effectively increasing the number of cells, reducing cell merging, and thus improving the closed porosity; but this is related to the amount of addition, and it is generally believed that the optimal amount of addition is 10-30% of calcium carbonate; and the present application needs an internal open structure and an external closed structure; therefore, the amount of addition is much less than that of the prior art, so that the nucleating agent mainly acts on the outside and cooperates with high-frequency microwave foaming to improve the closed porosity on the outside; and due to the small number of internal nucleation sites, the cells are easy to merge to form large-size open structures, which can instead improve the internal open porosity.

[0044] Silane enhances the interface bonding between inorganic fillers (calcium carbonate) and organic matrix, and assists in dispersion.

[0045] The capped isocyanate releases -NCO groups during the foaming stage, crosslinks with the resin to form urea bonds, and improves the closed porosity and flame retardancy.

[0046] In terms of process, the present application forms a high-closed-porosity surface by high-frequency microwave rapid foaming (calcium carbonate nucleation assistance) to block heat; low-frequency microwave slow-release foaming (water-soluble particle pore-forming) to form three-dimensional interconnected pores to dissipate energy through multiple sound reflections.

[0047] In order to further improve the surface closed porosity, thermoplastic glue powder is used to melt into a film under heat pressing to seal the surface pores to improve the thermal insulation performance.

[0048] The present application has at least the following beneficial technical effects:

[0049] The present application mainly controls the cell structure by microwave frequency foaming to present a high closed porosity on the surface and a high open porosity gradient inside, controls the foaming size by adding a nucleating agent, and forms micron-level interconnected pores by water washing after foaming to further optimize the sound absorption performance; finally, the surface is further improved by heat pressing to improve the surface closed porosity; so that the whole presents a foam structure with high closed porosity on the outside and high open porosity on the inside, external thermal insulation and internal noise reduction, and realizes the dual functions of thermal insulation and noise reduction. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0051] In the description of the present application, the terms "first", "second" are used only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0052] In the description of the present application, the term "for example" is used to indicate "as an example, illustration or explanation". Any embodiment described as "for example" in the present application is not necessarily interpreted as more preferred or more advantageous than other embodiments. The following description is given in order to enable any person skilled in the art to implement and use the present application. In the following description, details are listed for the purpose of explanation. It should be understood that those skilled in the art can realize the present application without using these specific details. In other examples, well-known structures and processes will not be described in detail in order to avoid unnecessary details making the description of the present application obscure. Therefore, the present application is not intended to be limited to the shown embodiments, but is consistent with the broadest scope of the principles and characteristics disclosed.

[0053] The experimental methods used in the specific embodiments are conventional methods, and the materials, reagents, etc. used are commercially available, unless otherwise specified.

[0054] In the present application, unless otherwise specified, "%" represents mass percentage; the raw materials, reagents, etc. used are conventional commercially available products.

[0055] The polyethylene glycol used in the present application is PEG-4000.

[0056] The water used in the present application is preferably pure water (RO water).

[0057] The water-soluble example used in the present application is sodium chloride or polyvinyl alcohol with an alcoholysis degree of 87% to 89%.

[0058] The calcium carbonate used in the present application is sieved through a 2500 mesh sieve after grinding.

[0059] The emulsifier used in the present application is sodium dodecyl sulfate.

[0060] The silane used in the present application is KH-570.

[0061] The blocked isocyanate used in the present application is blocked isophorone diisocyanate, hexamethylene diisocyanate and / or dicyclohexylmethane diisocyanate.

[0062] The glue powder used in the present application is low-density polyethylene with a particle size range of 20-100 μm.

[0063] The volatile blowing agent used in the present application is n-pentane.

[0064] Example 1

[0065] A preparation method of melamine foam resin, comprising the following steps:

[0066] S1 Preparation of prepolymer solution: take melamine and polyformaldehyde into a reaction kettle, adjust pH to 10.5 with NaOH; stir and heat to 85℃; add polydiethylene glycol to undergo hydroxymethylation reaction;

[0067] Keep the temperature and continuously stir the reaction for 120 min;

[0068] After the reaction is completed, cool to terminate the reaction to obtain a prepolymer solution;

[0069] The mass ratio of the melamine, polyformaldehyde and polydiethylene glycol is 100:30:4;

[0070] S2 Foaming synthesis: add sodium chloride, n-pentane, calcium carbonate, KH-570, isophorone diisocyanate, sodium dodecyl sulfate and formic acid into the prepolymer solution; stir to form a foaming solution;

[0071] The foaming solution is first foamed by 2450MHz microwave for 60s; then foamed by 915MHz for 120s;

[0072] After foaming, cure at 100℃ for 1h to obtain a preliminary foaming resin;

[0073] The addition amount of the sodium chloride, n-pentane, calcium carbonate, KH-570, isophorone diisocyanate, sodium dodecyl sulfate and formic acid is respectively 20%, 5%, 2%, 0.5%, 2% and 0.5% of the mass percentage of the prepolymer.

[0074] Sodium chloride: 20%

[0075] n-Pentane: 5%

[0076] Calcium carbonate: 2%

[0077] KH-570: 0.5%

[0078] Isophorone diisocyanate: 2%

[0079] Sodium dodecyl sulfate: 2%

[0080] Formic acid: 0.5%

[0081] S3 post-processing: the preliminary foaming resin is repeatedly washed in water; then hot air drying is performed, and after uniformly spraying low-density polyethylene on the surface, hot pressing is performed; the heat preservation and noise reduction foam material is obtained.

[0082] The amount of low-density polyethylene is 10% of the mass of the prepolymer; the temperature of hot pressing is 120°C, the duration is 5 min, the initial pressure is 5Mpa, and the uniform rise is to 10Mpa.

[0083] Example 2

[0084] A preparation method of melamine foam resin, comprising the following steps:

[0085] S1 preparation of prepolymer solution: melamine, paraformaldehyde are taken into a reaction kettle, and the pH is adjusted to 11.5 with NaOH; stirring and heating to 95°C; adding polyethylene glycol to undergo a methylolation reaction;

[0086] The temperature is maintained and the reaction is continuously stirred for 120 min;

[0087] After the reaction is completed, the reaction is terminated by cooling to obtain a prepolymer solution;

[0088] The mass ratio of the melamine, paraformaldehyde, and polyethylene glycol is 100:40:10;

[0089] S2 foaming synthesis: sodium chloride, n-pentane, calcium carbonate, KH-570, hexamethylene diisocyanate, sodium dodecyl sulfate, and formic acid are added to the prepolymer solution to form a foaming solution after stirring;

[0090] The foaming solution is first foamed by 2450MHz microwave for 90s; then foamed by 915MHz for 140s;

[0091] After foaming, the preliminary foaming resin is obtained after curing at 110°C for 1h;

[0092] The addition amount of the sodium chloride, n-pentane, calcium carbonate, KH-570, hexamethylene diisocyanate, sodium dodecyl sulfate, and formic acid is respectively:

[0093] Sodium chloride: 35%

[0094] n-Pentane: 10%

[0095] Calcium carbonate: 3.5%

[0096] KH-570: 1.0%

[0097] Hexamethylene diisocyanate: 3.0%

[0098] Sodium dodecyl sulfate: 3.5%

[0099] Formic acid: 1.2%

[0100] S3 post-processing: The initial foaming resin is repeatedly rinsed in water; then dried with hot air, and low-density polyethylene is evenly sprayed on the surface and then hot-pressed to obtain thermal insulation and noise reduction foam material.

[0101] The amount of low-density polyethylene used is 10% of the mass of the prepolymer; the hot-pressing temperature is 120℃, the duration is 5min, the initial pressure is 5MPa, and it is uniformly increased to 10MPa.

[0102] Example 3

[0103] A method for preparing melamine foam resin includes the following steps:

[0104] Preparation of S1 prepolymer solution: Melamine and paraformaldehyde were added to the reaction vessel, and the pH was adjusted to 11.5 with NaOH; the mixture was stirred and heated to 95°C; polyethylene glycol was added to induce a hydroxymethylation reaction;

[0105] Maintain the temperature and stir continuously for 120 minutes;

[0106] After the reaction is complete, the reaction is terminated by cooling, yielding a prepolymer solution.

[0107] The mass ratio of melamine, paraformaldehyde, and polyethylene glycol is 100:35:7;

[0108] S2 foaming synthesis: Polyvinyl alcohol, n-pentane, calcium carbonate, KH-570, dicyclohexylmethane diisocyanate, sodium dodecyl sulfate and formic acid are added to the prepolymer solution; the mixture is stirred until homogeneous to form a foaming solution;

[0109] The foaming liquid was first microwaved at 2450MHz for 90 seconds, and then foamed at 915MHz for 180 seconds.

[0110] After foaming, it is cured at 110℃ for 1 hour to obtain preliminary foamed resin;

[0111] The amounts of polyvinyl alcohol, n-pentane, calcium carbonate, KH-570, dicyclohexylmethane diisocyanate, sodium dodecyl sulfate, and formic acid added are respectively: percentages of the prepolymer's mass.

[0112] Polyvinyl alcohol: 50%

[0113] n-Pentane: 15%

[0114] Calcium carbonate: 5%

[0115] KH-570: 1.5%

[0116] Dicyclohexylmethane diisocyanate: 4.0%

[0117] Sodium dodecyl sulfate: 5.0%

[0118] Formic acid: 2.0%

[0119] S3 post-processing: the preliminary foaming resin is repeatedly washed in water; then hot air drying, uniform spraying of low density polyethylene on the surface is performed, and then hot pressing is performed; the thermal insulation and noise reduction foam material is obtained.

[0120] The amount of low density polyethylene is 10% of the mass of the prepolymer; the temperature of hot pressing is 120°C, the duration is 5 min, the initial pressure is 5Mpa, and the pressure is uniformly increased to 10Mpa.

[0121] Example 4

[0122] A method for preparing a melamine foam resin, which is different from example 1 in that:

[0123] No sodium chloride is added in step S2 foaming synthesis.

[0124] Example 5

[0125] A method for preparing a melamine foam resin, which is different from example 1 in that:

[0126] No calcium carbonate is added in step S2 foaming synthesis.

[0127] Example 6

[0128] A method for preparing a melamine foam resin, which is different from example 1 in that, step S3 is modified as:

[0129] S3 post-processing: the preliminary foaming resin is repeatedly washed in water; then hot air drying; the thermal insulation and noise reduction foam material is obtained.

[0130] Example 7

[0131] A method for preparing a melamine foam resin, which is different from example 1 in that, step S3 is modified as:

[0132] S3 post-processing: uniform spraying of low density polyethylene on the surface is performed, and then hot pressing is performed; the thermal insulation and noise reduction foam material is obtained.

[0133] The amount of low density polyethylene is 10% of the mass of the prepolymer; the temperature of hot pressing is 120°C, the duration is 5 min, the initial pressure is 5Mpa, and the pressure is uniformly increased to 10Mpa.

[0134] Example 8

[0135] A method for preparing a melamine foam resin, which is different from example 1 in that,

[0136] The parameters of microwave foaming in the foaming synthesis of step S2 are modified as follows:

[0137] The foaming liquid is foamed by 2450 MHz microwave for 180 s.

[0138] Example 9

[0139] A method for preparing melamine foam resin, which is different from example 1 in that,

[0140] The parameters of microwave foaming in the foaming synthesis of step S2 are modified as follows:

[0141] The foaming liquid is foamed by 915 MHz microwave for 180 s.

[0142] Example 10

[0143] In the foaming synthesis of step S2, n-pentane is replaced by azodicarbonamide with equal mass.

[0144] Example 11

[0145] A method for preparing melamine foam resin, which is different from example 1 in that,

[0146] In the foaming synthesis of step S2, the amount of calcium carbonate added is 10% of the mass of the prepolymer.

[0147] Step S3 is modified as follows:

[0148] S3 post-processing: after uniformly spraying low-density polyethylene on the surface, hot pressing is performed; and a heat-insulating and noise-reducing foam material is obtained.

[0149] The amount of low-density polyethylene used is 10% of the mass of the prepolymer; the temperature of hot pressing is 120°C, the duration is 5 min, the initial pressure is 5 Mpa, and it is uniformly increased to 10 Mpa.

[0150] Performance test

[0151] The products obtained in the above examples are subjected to performance tests, and the test items include:

[0152] Sound absorption coefficient: according to the method recorded in “GB / T 18696.2-2002 Acoustics-Determination of sound absorption coefficients and impedance in impedance tubes-Part 2: Transfer-function method”. The sample size is 29 mm in diameter and 30 mm in length.

[0153] Thermal conductivity: according to the method recorded in “GB / T 10295-2008 Thermal insulation materials-Determination of steady-state thermal resistance and related properties-Heat flow meter method”.

[0154] The test results are shown in Table 1.

[0155] Table 1

[0156]

[0157] As shown in Table 1, in the present application:

[0158] Examples 1, 2 and 3 have a slight increase in thermal conductivity (i.e. a slight decrease in thermal insulation effect) as the content of calcium carbonate increases; meanwhile, due to the higher proportion of foaming agent and water-soluble particles added, the sound absorption coefficient increases (better sound insulation effect).

[0159] In Example 4, no water-soluble particles are added, which greatly enhances the role of calcium carbonate as a nucleating agent, and the closed cell rate is greatly improved, and the internal cannot form a through channel. The sound absorption coefficient decreases significantly.

[0160] In Example 5, no calcium carbonate is added, and the thermal conductivity of calcium carbonate is relatively high, so its absence can improve the thermal insulation; but at the same time, it is difficult to control the size of the internal pores, resulting in a slight decrease in the sound absorption coefficient; however, the hot pressing post-processing step of the present application can improve the thermal insulation, so the advantages brought by the absence of calcium carbonate cannot compensate for its disadvantages.

[0161] In Example 6, no hot pressing post-processing is performed, so the surface closed cell rate only relies on frequency division microwave foaming and nucleating agent, which can improve the sound absorption coefficient, but at the same time, the thermal conductivity also increases significantly, which cannot achieve the effect of thermal insulation.

[0162] In Example 7, the water-soluble ions are not washed away, resulting in their retention inside; which increases the number of small heat-conducting channels and blocked gaps inside, resulting in a significant deterioration of performance.

[0163] Examples 8 and 9 both do not have frequency division foaming, and the long high-frequency foaming time leads to the merging of bubbles, and the open cell rate decreases; at the same time, the density may increase due to the collapse of the bubbles; while low-frequency foaming leads to incomplete foaming and uneven distribution of bubbles, affecting the uniformity of sound absorption; and the loose bubble structure may reduce the heat insulation performance. Therefore, the sound insulation and thermal insulation performance of Examples 8 and 9 are not as good as Example 1.

[0164] Example 10 uses azodicarbonamide as the foaming agent; due to the different mechanism, the generated foam has a high closed cell rate; therefore, the thermal insulation effect is better; but because the inside and outside both have a high closed cell rate, the sound insulation effect decreases significantly.

[0165] Example 11 uses an excessive amount of calcium carbonate nucleating agent, which greatly increases the closed cell rate; although theoretically it helps to reduce the thermal conductivity; but the calcium carbonate remains inside the foam, which has high thermal conductivity, which will also cause the thermal conductivity to increase; from the experimental results, the increase is much greater than the decrease, resulting in a significant deterioration of sound insulation and thermal insulation performance.

[0166] The above detailed description is a specific description of one of the possible embodiments of the present application, which is not used to limit the patent scope of the present application, and any equivalent implementation or change made without departing from the present application shall be included in the scope of the technical solutions of the present application.

Claims

1. A method of making a thermal and noise reducing foam material, characterized in that, The method comprises the following steps: S1: preparation of a prepolymer solution: melamine and paraformaldehyde are added into a reaction kettle, and the pH is adjusted to 10.5-11.5 with a strong base; stirring and heating are performed, and polyethylene glycol is added; a methylolation reaction is performed; after the reaction is completed, the reaction is terminated by cooling to obtain a prepolymer solution; The mass ratio of the melamine, the paraformaldehyde and the polyethylene glycol is 100:30-40:4-10; S2: foaming synthesis: water-soluble particles, a volatile foaming agent, calcium carbonate, silane, blocked isocyanate, an emulsifier and formic acid are added into the prepolymer solution; stirring is performed to form a foaming liquid; The foaming liquid is foamed by high-frequency microwave foaming and then by low-frequency foaming, and the frequency difference between the two foaming processes is at least 1000 MHz; After foaming, high-temperature curing is performed to obtain a preliminary foaming resin; The water-soluble particles, the volatile foaming agent, the calcium carbonate, the silane, the isocyanate, the emulsifier and the formic acid are added in the following amounts based on the mass percentage of the prepolymer: Water-soluble particles: 20-50% Volatilization foaming agent: 5-15% Calcium carbonate: 2-5% Silane: 0.5-1.5% Blocked isocyanate: 2-4% Emulsifier: 2-5% Formic acid: 0.5-2% S3: post-treatment: the preliminary foaming resin is placed into water to wash away the water-soluble particles; then, drying is performed, and hot pressing is performed after the surface is sprayed with a glue powder; A heat-insulating and noise-reducing foaming material is obtained; The water-soluble particles are inorganic salts or water-soluble polymers; The glue powder is a thermoplastic polymer; the particle size is 20-100 μm; In the preparation of the step S2, the high-frequency microwave foaming time is 60-90 s; the low-frequency foaming time is 120-180 s; the high-temperature curing temperature is 100-120 ℃, and the high-temperature curing time is ≥1 h; In the preparation of the S3 post-treatment, the addition amount of the glue powder is at least 10% based on the mass percentage of the prepolymer.

2. The method of claim 1, wherein the temperature control and noise reduction foam is prepared by the steps of: The molecular weight of the polyethylene glycol is ≤4000.

3. The method of claim 1, wherein the temperature retaining and noise reducing foam material is prepared by the steps of: The particle size of the calcium carbonate is ≤5 μm.

4. The method of claim 1, wherein the temperature retaining and noise reducing foam material is prepared by the steps of: The emulsifier is an anionic surfactant.

5. The method of claim 1, wherein the temperature control and noise reduction foam is prepared by the steps of: The blocked isocyanate is blocked isophorone diisocyanate, hexamethylene diisocyanate and / or dicyclohexylmethane diisocyanate.

6. The method of claim 1, wherein the temperature control and noise reduction foam is prepared by the steps of: In the preparation of the step S1, the methylolation reaction temperature is 85-110 ℃, and the time is at least 120 min.

7. The method for preparing the thermal insulation and noise reduction foam material according to claim 1, characterized in that, In the preparation of the S3 post-treatment, the hot pressing temperature is ≥120 ℃, and the heat preservation time is at least 5 min.

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