Composition, composite foam material and method for producing the same, refrigerator

Abstract

The application discloses a composition, a composite foaming material and a preparation method thereof and a refrigerator, and relates to the technical field of foaming materials. The composition comprises a first component and a second component. The first component comprises a combined polyether, a foaming agent and a microencapsulated catalyst. The microencapsulated catalyst comprises a core and a shell layer covering the core. The material of the core comprises an amine catalyst and a metal catalyst. The material of the shell layer comprises a polymer. The second component comprises an isocyanate. The composition provided by the application can optimize the foaming performance, and polyurethane foam with environmental protection, low thermal conductivity, low density, high flow, rapid demolding and high strength can be obtained through foaming preparation.

Description

Technical Field

[0001] This application relates to the field of foaming materials technology, and in particular to a composition, a composite foaming material and its preparation method, and a refrigerator. Background Technology

[0002] As the refrigerator industry transforms towards "new energy efficiency, thinner profiles, lower costs, and higher efficiency," polyurethane foam systems face multiple coupled performance requirements: new energy efficiency standards require lower thermal conductivity of foam, ultra-thin refrigerators require foam systems with excellent flowability to fill complex cavities, manufacturing cost control requires lower foam density and lower raw material costs, production efficiency improvement requires shorter demolding time, and at the same time, it is necessary to meet global environmental policies to replace high GWP hydrofluorocarbon (HFC) foaming agents.

[0003] Based on the above requirements, the composition of composite foam materials needs to be further improved in order to enhance their performance. Summary of the Invention

[0004] In view of this, this application provides a composition, a composite foaming material and a method for preparing the same, and a refrigerator.

[0005] The embodiments of this application are implemented as follows: a composition comprising a first component and a second component.

[0006] The first component includes a polyether, a foaming agent, and a microencapsulated catalyst. The microencapsulated catalyst includes a core and a shell covering the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers.

[0007] The second component includes isocyanate.

[0008] Optionally, in some embodiments of this application, the average particle size of the microencapsulated catalyst is 5 μm to 20 μm.

[0009] The average particle size of the kernel is 3μm to 16μm.

[0010] The average thickness of the shell is 1 μm to 2 μm.

[0011] The amine catalyst includes one or more of dimethylcyclohexylamine, triethylenediamine, and N,N-dimethylbenzylamine.

[0012] The metal catalyst includes one or more of dibutyltin dilaurate, stannous octoate, and bismuth isooctanoate.

[0013] The polymer includes one or more of polyurea, polyamide, and polyurethane.

[0014] In the microencapsulated catalyst, the mass ratio of the amine catalyst, the metal catalyst and the polymer is (40~50):(10~20):(30~50).

[0015] Optionally, in some embodiments of this application, the functionality of the combined polyether is 2.5 to 3.

[0016] The combined polyether includes one or more of polyether polyols, polyester polyols, and aromatic polyether polyols.

[0017] The foaming agent includes cyclopentane, isobutane, and 2-methylpentane.

[0018] The foaming agent also includes an auxiliary nucleating agent. The auxiliary nucleating agent includes HFO-1233zd.

[0019] In the foaming agent, the mass ratio of cyclopentane, isobutane, 2-methylpentane and the auxiliary nucleating agent is (60~80):(15~25):(3~8):(0.5~1.5).

[0020] Optionally, in some embodiments of this application, the first component further includes a nano-reinforcing agent.

[0021] The first component also includes silicone oil.

[0022] The first component also includes water.

[0023] Optionally, in some embodiments of this application, at least one of the following features (1) to (2) is also included: (1) The surface hydroxyl content of the nano-reinforcing agent is less than or equal to 0.3 wt%.

[0024] The nano-reinforcing agent comprises silane coupling agent-modified nanomaterials. The average particle size of the nanomaterials is 50 nm to 100 nm.

[0025] The silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane.

[0026] The nanomaterials include one or more of calcium carbonate, talc, and silicon dioxide.

[0027] (2) The HLB value of the silicone oil is 4~6.

[0028] The surface tension of the silicone oil is 20mN / m to 25mN / m.

[0029] The silicone oil includes one or more of polyether-modified silicone oil and fluorine-modified silicone oil.

[0030] Optionally, in some embodiments of this application, the first component, by weight, includes: 100 parts of the combined polyether, 8-15 parts of the foaming agent, 0.8-1.5 parts of the microencapsulated catalyst, 1-3 parts of the nano-reinforcing agent, 1.2-1.8 parts of the silicone oil, and 0.6-1 parts of the water.

[0031] The isocyanate has an NCO content of 28% to 32%.

[0032] The viscosity of the isocyanate is 180 mPa·s to 220 mPa·s.

[0033] The isocyanate includes polycarbonate polyol modified isocyanate.

[0034] The mass ratio of the polyether to the isocyanate is 100:(130~150).

[0035] Accordingly, this application also provides a method for preparing a composite foamed material, comprising the following steps: providing a first component and a second component; and performing a foaming treatment on the first component and the second component to obtain a composite foamed material.

[0036] The first component comprises a polyether combination, a blowing agent, and a microencapsulation catalyst. The microencapsulation catalyst includes a core and a shell encapsulating the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers. The second component comprises isocyanate.

[0037] Optionally, in some embodiments of this application, the storage temperature of the first component is 28°C to 32°C.

[0038] The storage temperature for the second component is 8℃~12℃.

[0039] Before mixing the first component and the second component, the method further includes: preheating the first component to a first temperature and preheating the second component to a second temperature. The temperature difference between the first temperature and the second temperature is 18°C ​​to 23°C, the first temperature is 35°C to 40°C, and the second temperature is 15°C to 20°C.

[0040] Optionally, in some embodiments of this application, the foaming process includes a foam injection stage, a filling stage, and a curing stage performed sequentially within the mold. The foaming stage includes: injecting the first component and the second component, and mixing the first component and the second component. The pressure for injecting the first component and the second component is 101 kPa to 103 kPa, the pressure for mixing the first component and the second component is 10 MPa to 15 MPa, and the mixing time is 8 s to 12 s.

[0041] The filling stage includes: reducing the pressure to a first pressure within a first time period, reducing the pressure to a second pressure within a second time period, and maintaining the pressure for a third time period. The first time period is 1s to 3s, the first pressure is 82kPa to 88kPa, the second time period is 4s to 6s, the second pressure is 65kPa to 70kPa, and the third time period is 10s to 15s.

[0042] The curing stage includes: holding at a third pressure for a fourth time period, and holding at a fourth pressure for a fifth time period. The third pressure is 65 kPa to 70 kPa, the fourth time period is 30 to 40 seconds, the fourth pressure is 101 kPa to 103 kPa, and the fifth time period is 2.5 to 3 minutes.

[0043] The temperature of the cavity wall of the mold is greater than the temperature of the middle part of the mold. Specifically, the temperature of the cavity wall of the mold is 28℃~30℃, and the temperature of the middle part of the mold is 22℃~25℃.

[0044] Accordingly, this application also provides a composite foaming material prepared by the above-described preparation method.

[0045] Accordingly, this application also provides a refrigerator, including a cabinet, the interlayer of which is provided with the above-mentioned composite foam material, or includes the composite foam material prepared by the above-mentioned preparation method.

[0046] The composition provided in this application includes a first component and a second component, which can be used to prepare polyurethane foam. The microencapsulated catalyst in the first component has a core-shell structure, with the core being a composite of an amine catalyst and a metal catalyst, and the shell being a polymer material. The core-shell structure can isolate the core from direct contact with the combined polyether and the blowing agent, and can rupture and release under specific mixing pressure to play a catalytic role, thus solving the contradiction of storage stability. The shell layer prevents the amine catalyst and the metal catalyst from reacting and becoming ineffective with the combined polyether and the blowing agent in a premature manner, extending the storage period of the raw materials. It can achieve "on-demand catalysis". During mixing, the shell layer is ruptured by a certain mechanical shear force to precisely release the amine catalyst and the metal catalyst, and control the milky white time and gel time. It can also improve process adaptability. The composite catalytic system of amine catalyst and metal catalyst can balance the foaming and curing rates. With a certain foaming process, the demolding time can be effectively shortened. The configuration of the composition can also optimize the foam performance. Through foaming preparation, polyurethane foam with environmental friendliness, low thermal conductivity, low density, high flowability, fast demolding and high strength can be obtained. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart of a method for preparing a composite foamed material provided in an embodiment of this application. Detailed Implementation

[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0050] In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operating state, specifically the orientation shown in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative purposes and do not impose numerical requirements or establish a numerical order.

[0051] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0052] In this application, "at least one" means one or more, and "more than one" means two or more. "One or more", "at least one of the following", or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0053] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0054] Existing foaming systems have at least the following problems: 1. Regarding the foaming agent system, cyclopentane single system has high density and is easily deformed at low temperature, butane has poor solubility and is easy to escape, binary compound system is difficult to balance low thermal conductivity and high flow performance at the same time, some ternary compound schemes introduce HFO foaming agents, but the dosage is too high, which leads to increased costs. 2. In terms of the balance between curing and strength, the direct addition of traditional catalysts can easily lead to reaction failure during storage, and single isocyanate modification cannot achieve both rapid demolding and high foam strength. 3. In terms of process adaptability, atmospheric pressure foaming has insufficient fluidity, and the entire negative pressure process is prone to foaming agent loss and cell rupture, which cannot meet the filling requirements of ultra-thin refrigerator cavity. 4. Performance coupling contradictions are prominent. It is difficult to coordinate and optimize low density and high strength, high flow and low thermal conductivity, and rapid demolding and dimensional stability. Existing technologies have not formed a systematic solution.

[0055] The technical solution of this application solves at least one of the above-mentioned problems.

[0056] The technical solution of this application is as follows: In a first aspect, embodiments of this application provide a composition comprising a first component and a second component.

[0057] The first component includes a polyether, a foaming agent, and a microencapsulated catalyst. The microencapsulated catalyst includes a core and a shell covering the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers.

[0058] The second component includes isocyanate.

[0059] It is understood that the first component is the white component for synthesizing polyurethane foam, and the second component is the black component for synthesizing polyurethane foam. The white and black components are mixed and reacted to form polyurethane foam.

[0060] The composition provided in this application includes a first component and a second component, which can be used to prepare polyurethane foam. The microencapsulated catalyst in the first component has a core-shell structure, with the core being a composite of an amine catalyst and a metal catalyst, and the shell being a polymer material. The core-shell structure can isolate the core from direct contact with the combined polyether and the blowing agent, and can rupture and release under specific mixing pressure to play a catalytic role, thus solving the contradiction of storage stability. The shell layer prevents the amine catalyst and the metal catalyst from reacting and becoming ineffective with the combined polyether and the blowing agent in a premature manner, extending the storage period of the raw materials. It can achieve "on-demand catalysis". During mixing, the shell layer is ruptured by a certain mechanical shear force to precisely release the amine catalyst and the metal catalyst, and control the milky white time and gel time. It can also improve process adaptability. The composite catalytic system of amine catalyst and metal catalyst can balance the foaming and curing rates. With a certain foaming process, the demolding time can be effectively shortened. The configuration of the composition can also optimize the foam performance. Through foaming preparation, polyurethane foam with environmental friendliness, low thermal conductivity, low density, high flowability, fast demolding and high strength can be obtained.

[0061] In some embodiments, the amine catalyst includes one or more of dimethylcyclohexylamine, triethylenediamine, and N,N-dimethylbenzylamine.

[0062] In some embodiments, the metal catalyst includes one or more of dibutyltin dilaurate, stannous octoate, and bismuth isooctanoate.

[0063] In some embodiments, the polymer includes one or more of polyurea, polyamide, and polyurethane.

[0064] For example, the microencapsulated catalyst comprises a core formed of dimethylcyclohexylamine and dibutyltin dilaurate, and a polyurea shell covering the core.

[0065] In some embodiments, the average particle size of the microencapsulated catalyst is 5 μm to 20 μm, for example, it can be 5 μm, 8 μm, 10 μm, 15 μm, 20 μm or any two of the above values.

[0066] Furthermore, the average particle size of the core is 3 μm to 16 μm, for example, it can be 3 μm, 5 μm, 8 μm, 10 μm, 15 μm, 16 μm, or any range between two of the above values. Within the range of the average particle size of the core, the amine catalyst and the metal catalyst can exert good catalytic function.

[0067] The average thickness of the shell layer is 1 μm to 2 μm, for example, it can be 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2 μm, or any two of the above values. Within the range of the average thickness of the shell layer, the storage stability of the microencapsulated catalyst can be ensured, and the shell layer can be ruptured under appropriate pressure during the preparation of polyurethane foam to expose the amine catalyst and the metal catalyst to exert their catalytic effect.

[0068] In some embodiments, the mass ratio of the amine catalyst, the metal catalyst, and the polymer in the microencapsulated catalyst is (40-50):(10-20):(30-50), for example, 40:15:50, 42:12:45, 45:10:40, 48:18:35, 50:20:30, or any range between two of the above ratios. Within this mass ratio range, it is beneficial for the amine catalyst and the metal catalyst to work synergistically to improve the catalytic effect, and for the polymer to be effectively encapsulated and protected.

[0069] In some embodiments, the functionality of the polyether composition is 2.5 to 3, for example, it can be 2.5, 2.6, 2.7, 2.8, 2.9, 3, or any range between two of the above values. It should be noted that the higher the functionality of the polyether composition, the higher its hydroxyl content, which means that the polyether composition has better reactivity and processability.

[0070] In some embodiments, the combined polyether comprises one or more of polyether polyols, polyester polyols, and aromatic polyether polyols.

[0071] For example, in one specific embodiment, the combined polyether comprises, by weight, 60-70 parts of polyether polyol, 20-30 parts of polyester polyol, and 5-10 parts of aromatic polyether polyol.

[0072] In some embodiments, the blowing agent includes cyclopentane (CP), isobutane (i-C4), and 2-methylpentane (2-MP). This application employs a ternary compound blowing agent, overcoming the limitations of traditional binary compound agents. The branched structure of 2-methylpentane reduces the viscosity of the foaming system, improves fluidity, synergistically reduces cell density with isobutane, and synergistically reduces thermal conductivity and improves environmental friendliness with cyclopentane.

[0073] In some embodiments, the foaming agent further includes an auxiliary nucleating agent. The auxiliary nucleating agent is beneficial for further promoting the foaming and nucleation of the composition, thereby improving the nucleation quality.

[0074] Furthermore, the auxiliary nucleating agent includes HFO-1233zd.

[0075] In some embodiments, the mass ratio of the cyclopentane, isobutane, 2-methylpentane, and the auxiliary nucleating agent in the foaming agent is (60~80):(15~25):(3~8):(0.5~2), for example, 60:20:5:2, 65:18:6:1.2, 70:15:8:1, 75:22:3:0.8, 80:25:4:0.5, or any range between two of the above ratios. Within this mass ratio range, it is beneficial for the foaming agent to achieve high-quality foaming.

[0076] In some embodiments, the first component further includes a nano-reinforcing agent.

[0077] In some embodiments, the surface hydroxyl content of the nano-reinforcing agent is less than or equal to 0.3 wt%, for example, it can be 0.3 wt%, 0.2 wt%, 0.1 wt%, or lower. Within the range of the surface hydroxyl content of the nano-reinforcing agent, the nano-reinforcing agent exhibits good compatibility with polyurethane foam. It should be noted that the surface hydroxyl content of the nano-reinforcing agent refers to the mass of hydroxyl groups divided by the mass of the nano-reinforcing agent.

[0078] In some embodiments, the nano-reinforcing agent comprises silane coupling agent-modified nanomaterials.

[0079] Furthermore, the silane coupling agent includes one or more of γ-aminopropyltriethoxysilane (KH-550), γ-glycidoxypropyltrimethoxysilane (KH-560), and γ-methacryloyloxypropyltrimethoxysilane (KH-570).

[0080] In some embodiments, the average particle size of the nanomaterial is 50 nm to 100 nm, for example, it can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, or any range between two of the above values. Within the range of the average particle size of the nanomaterial, the nanomaterial has good processability, can fill defects in the cell walls of polyurethane foam, and improve the strength and dimensional stability of polyurethane foam.

[0081] In some embodiments, the nanomaterial includes one or more of calcium carbonate, talc, and silicon dioxide.

[0082] The silane coupling agent modified nanomaterial can fill tiny defects in the foam cell walls, reduce pores and stress concentration, improve foam compression strength, reduce foam low-temperature deformation rate, enhance the structural stability of the ultra-thin refrigerator body, prevent body deformation in low-temperature environments, refine the foam cell structure, help improve the foam closed-cell rate, further reduce the thermal conductivity, and help meet the new energy efficiency standards.

[0083] In some embodiments, the first component further includes silicone oil.

[0084] In some embodiments, the HLB value of the silicone oil is 4 to 6, for example, it can be 4, 4.5, 5, 5, 6, or any range between two of the above values. It should be noted that the HLB value represents the hydrophilic-lipophilic balance, which is a physicochemical parameter characterizing the relative strength of the hydrophilicity and lipophilicity of the silicone oil.

[0085] In some embodiments, the surface tension of the silicone oil is 20mN / m to 25mN / m, for example, it can be 20mN / m, 21mN / m, 22mN / m, 23mN / m, 24mN / m, 25mN / m or any range between two of the above values.

[0086] Thus, under the aforementioned conditions, the silicone oil has high fluidity, which can promote the flow of foam and ensure uniform foam dispersion.

[0087] Furthermore, the silicone oil includes one or more of polyether-modified silicone oil and fluorine-modified silicone oil.

[0088] In some embodiments, the first component further includes water. It is understood that water is used as a solvent.

[0089] In some embodiments, the first component, by mass parts, comprises: The composition includes 100 parts of polyether, 8-15 parts of foaming agent, 0.8-1.5 parts of microencapsulated catalyst, 1-3 parts of nano-reinforcing agent, 1.2-1.8 parts of silicone oil, and 0.6-1 parts of water.

[0090] Thus, within the range of mass fractions of each raw material in the first component, it is beneficial for the components to work together to improve the stability of the first component and the quality of nucleation and foaming of the first and second components.

[0091] In some embodiments, the NCO content of the isocyanate is 28% to 32%, for example, it can be 28%, 29%, 30%, 31%, 32%, or any range between two of the above values. It should be noted that the NCO content of the isocyanate refers to the mass percentage of isocyanate (-NCO) groups contained in 100g of isocyanate.

[0092] In some embodiments, the viscosity of the isocyanate is 180 mPa·s to 220 mPa·s, for example, it can be 180 mPa·s, 185 mPa·s, 190 mPa·s, 195 mPa·s, 200 mPa·s, 210 mPa·s, 220 mPa·s, or a range between any two of the above values. It should be noted that the viscosity in this application represents the force required to move two fluid layers 1 meter apart relative to each other at a speed of 1 meter per second at 25°C.

[0093] Under the above conditions, isocyanates exhibit suitable properties and are suitable for preparing polyurethane foams.

[0094] In some embodiments, the isocyanate comprises a polycarbonate polyol-modified isocyanate. After modification with polycarbonate polyol, the isocyanate exhibits better compatibility with the first component.

[0095] In some embodiments, the mass ratio of the combined polyether to the isocyanate is 100:(130~150), for example, it can be 100:130, 100:135, 100:140, 100:145, 100:150, or any range between two of the above ratios. Within the range of the above mass ratio, it is beneficial for the combined polyether and the isocyanate to co-foam in the preparation of polyurethane foam, thereby increasing the yield and avoiding waste of raw materials.

[0096] Secondly, please refer to Figure 1 This application also provides a method for preparing a composite foamed material, comprising the following steps: Step S11: Provide the first component and the second component; Step S12: Perform foaming treatment on the first component and the second component to obtain a composite foam material.

[0097] The first component includes a polyether, a foaming agent, and a microencapsulated catalyst. The microencapsulated catalyst includes a core and a shell covering the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers. The second component includes isocyanate.

[0098] It should be noted that the first and second components can refer to the composition in the first aspect above, and will not be repeated here.

[0099] In some embodiments, the storage temperature of the first component is 28°C to 32°C, for example, it can be 28°C, 29°C, 30°C, 31°C, 32°C or any two of the above values.

[0100] The storage temperature of the second component is 8℃~12℃, for example, it can be 8℃, 9℃, 10℃, 11℃, 12℃ or any two of the above values.

[0101] It should be noted that the preparation method of the first component and the second component involves mixing the raw materials and storing them at a certain temperature. A dynamic temperature-controlled storage process is selected based on the composition of the first component and the second component to improve the storage stability of the first component and the second component.

[0102] It should also be noted that the microencapsulated catalyst can be prepared by interfacial polymerization. Specifically, an amine catalyst and a metal catalyst are first mixed uniformly in a certain proportion to obtain a composite catalyst, and then polymer monomers are polymerized on the surface of the composite catalyst droplets to form a shell.

[0103] In some embodiments, before mixing the first component and the second component, the method further includes: preheating the first component to a first temperature and preheating the second component to a second temperature.

[0104] In some embodiments, the temperature difference between the first temperature and the second temperature is 18°C ​​to 23°C, for example, it can be 18°C, 19°C, 20°C, 21°C, 22°C, 23°C or any two of the above values.

[0105] Furthermore, the first temperature is 35℃~40℃, for example, it can be 35℃, 36℃, 37℃, 38℃, 39℃, 40℃ or any range between two of the above values.

[0106] The second temperature is 15℃~20℃, for example, it can be 15℃, 16℃, 17℃, 18℃, 19℃, 20℃ or any range between two of the above values.

[0107] Preheating the first and second components before mixing helps improve their activity and facilitates preparation for foaming. Maintaining a certain temperature difference can prevent poor compatibility of the components after mixing and the easy volatilization and escape of some components.

[0108] In some embodiments, the foaming process includes a foam injection stage, a filling stage, and a curing stage performed sequentially within the mold. It can be understood that the foam injection stage is the process of injecting the first component and the second component together into the foaming mold and mixing them; the filling stage is the process of the first component and the second component flowing and filling the foaming mold to form the mold shape; the curing stage is the process of the flowing raw materials solidifying after filling; and finally, demolding yields a polyurethane foam composite foam material.

[0109] In some embodiments, the foaming stage includes: injecting the first component and the second component, and mixing the first component and the second component.

[0110] Furthermore, the pressure at which the first component and the second component are injected is atmospheric pressure, for example, 101 kPa to 103 kPa.

[0111] The pressure for mixing the first component and the second component is 10MPa to 15MPa, for example, it can be 10MPa, 11MPa, 12MPa, 13MPa, 14MPa, 15MPa or any range between two of the above values; the time for mixing the first component and the second component is 8s to 12s, for example, it can be 8s, 9s, 10s, 11s, 12s or any range between two of the above values.

[0112] Under the conditions described above during the foaming stage, it is beneficial for the first component and the second component to be fully and evenly mixed.

[0113] It should be noted that after mixing the first and second components at a relatively high pressure, the pressure needs to be reduced to atmospheric pressure before the filling stage can proceed.

[0114] In some embodiments, the filling stage includes: reducing the pressure to a first pressure during a first time period, reducing the pressure to a second pressure during a second time period, and maintaining the pressure for a third time period.

[0115] Furthermore, the first time period is 1s to 3s, for example, it can be 1s, 2s, 3s or any range between the two values ​​mentioned above.

[0116] The first pressure is 82 kPa to 88 kPa, for example, it can be 82 kPa, 83 kPa, 84 kPa, 85 kPa, 86 kPa, 87 kPa, 88 kPa or any range between two of the above values.

[0117] The second time period is 4s to 6s, for example, it can be 4s, 5s, 6s or any range between the two values ​​mentioned above.

[0118] The second pressure is 65 kPa to 70 kPa, for example, it can be 65 kPa, 66 kPa, 67 kPa, 68 kPa, 69 kPa, 70 kPa or any two of the above values.

[0119] The third time period is 10s to 15s, for example, it can be 11s, 12s, 13s, 14s, 15s or any range between two of the above values.

[0120] Thus, under the conditions of the filling stage described above, pressure control using gradient negative pressure can avoid instantaneous loss of foaming agent and cell rupture, thereby improving foaming quality.

[0121] In some embodiments, the curing stage includes: holding at a third pressure for a fourth time period, and holding at a fourth pressure for a fifth time period.

[0122] Furthermore, the third pressure is the same as the second pressure. Specifically, the third pressure is 65 kPa to 70 kPa, for example, it can be 65 kPa, 66 kPa, 67 kPa, 68 kPa, 69 kPa, 70 kPa, or any range between two of the above values.

[0123] The fourth time period is 30s to 40s, for example, it can be 30s, 32s, 35s, 38s, 40s or any range between two of the above values.

[0124] The fourth pressure is atmospheric pressure, for example, it can be 101kPa~103kPa.

[0125] The fifth time period is 2.5 min to 3 min, for example, it can be 2.5 min, 2.6 min, 2.7 min, 2.8 min, 2.9 min, 3 min or any range between two of the above values.

[0126] Thus, under the conditions of the aforementioned curing stage, the foaming quality can be improved.

[0127] In some embodiments, the temperature of the cavity wall of the mold is greater than the temperature of the middle portion of the mold. It should be noted that the middle portion of the mold refers to the part in the center of the mold that is far from the cavity wall.

[0128] Specifically, the temperature of the cavity wall of the mold is 28℃~30℃, for example, it can be 28℃, 28.5℃, 29℃, 29.5℃, 30℃, or any two of the above values; the temperature of the middle part of the mold is 22℃~25℃, for example, it can be 22℃, 22.5℃, 23℃, 23.5℃, 24℃, 24.5℃, 25℃, or any two of the above values. By controlling the temperature of the cavity wall and the middle part, the foam can be guided to flow from the cavity wall to the middle part, solving the problem of narrow cavity and filling difficulty in ultra-thin refrigerators, while refining the cell structure.

[0129] The method for preparing the composite foamed material disclosed in this application employs a synergistic modification of a microencapsulated composite catalyst and a nano-reinforcing agent. Microencapsulation technology enables "on-demand catalysis," shortening demolding time. The nano-reinforcing agent fills cell defects, improving strength and low-temperature stability, thus resolving the contradiction between rapid demolding and high strength and dimensional stability. A ternary synergistic foaming system is used, where the branched structure of 2-methylpentane reduces system viscosity, synergistically reducing density with isobutane, and HFO-1233zd refines the cell structure. Dynamic temperature control and partial storage address the compatibility issues of the ternary components, achieving a synergistic effect of low thermal conductivity, low density, and high flowability. A gradient negative pressure-mold temperature control coupling process is employed. Gradient negative pressure avoids instantaneous loss of the foaming agent, while zoned mold temperature control guides foam flow, solving the problems of narrow cavities and filling difficulties in ultra-thin refrigerators, further refining the cell structure and reducing thermal conductivity. The resulting composite foamed material can meet the refrigerator industry's transformation needs for "new energy efficiency, thinness, low cost, and high efficiency."

[0130] Thirdly, embodiments of this application also provide a composite foaming material, which is prepared by the above-described preparation method.

[0131] The composite foaming material provided in this application embodiment can meet the requirements of environmental protection and low thermal conductivity, satisfying the requirements of the new energy efficiency standards; achieve a balance between low density and high strength, avoiding insufficient structural support for ultra-thin refrigerator cabinets; high fluidity adapts to thinness, ensuring that the complex cavities of ultra-thin refrigerators are filled without dead corners, avoiding local voids; and rapid demolding improves efficiency, reduces production cycle time, and increases production capacity; in addition, there is no need to modify existing production equipment, reducing raw material costs and taking into account both industrial feasibility and economy.

[0132] Fourthly, embodiments of this application also provide a refrigerator, which includes a cabinet, and the interlayer of the cabinet is provided with the above-mentioned composite foam material, or the composite foam material prepared by the above-mentioned preparation method.

[0133] In addition to refrigerator insulation, the composite foam material provided in this application embodiment can also be widely used in cold chain equipment such as cold chain containers and refrigerated trucks, and has broad market application prospects.

[0134] The present application will be specifically described below through specific embodiments. The following embodiments are only some embodiments of the present application and are not intended to limit the present application.

[0135] Example 1 This embodiment provides a composite foaming material, and the preparation method of the composite foaming material is as follows: Step S21: Preparation of the first component: by weight: 100 parts of combined polyether (65 parts of polyether polyol, 25 parts of polyester polyol, 10 parts of aromatic polyether polyol, functionality 2.8), 12 parts of ternary synergistic foaming agent (70wt% cyclopentane, 22wt% isobutane, 6wt% 2-methylpentane, 1.2wt% HFO-1233zd), 1.0 part of microencapsulation catalyst (45wt% dimethylcyclohexylamine and 15wt% dibutyltin dilaurate core, 40wt% polyurea shell, average particle size 10μm), 1.5 parts of polyether modified silicone oil (HLB value 5, surface tension 23mN / m), 0.8 parts of water, and 2 parts of KH-550 modified nano calcium carbonate (average particle size 80nm, surface hydroxyl content 0.2wt%). After mixing all raw materials, stir at a constant temperature for 35min at a speed of 70r / min, and store at 30℃ for later use. The second component was prepared as follows: 140 parts of polycarbonate polyol prepolymer modified isocyanate (NCO content 29%, viscosity 200 mPa·s / 25℃), which was degassed under vacuum for 18 min after prepolymer modification, with a vacuum degree of -0.085 MPa, and stored at 10℃ for later use. Step S22: Preheat the first component to 36°C and the second component to 17°C, and inject them together into the foaming mold. The mold cavity wall temperature is 29°C and the middle temperature is 23°C. During the foaming stage, the pressure is 102 kPa, and then mixed at 13 MPa for 10 seconds. During the filling stage, the pressure is reduced to 85 kPa within 3 seconds, and then reduced to 68 kPa within 5 seconds, and held for 12 seconds. After filling, the pressure is maintained at 68 kPa for 35 seconds to cure, and then restored to 102 kPa for 2.8 minutes to cure. The material is then demolded for 3.2 minutes to obtain the composite foam material.

[0136] Example 2 Step S31: Preparation of the first component: by weight: 100 parts of combined polyether (60 parts of polyether polyol, 30 parts of polyester polyol, 10 parts of aromatic polyether polyol, functionality 2.5), 15 parts of ternary synergistic foaming agent (65wt% cyclopentane, 25wt% isobutane, 8wt% 2-methylpentane, 2wt% HFO-1233zd), 1.5 parts of microencapsulated catalyst (50wt% triethylenediamine and 10wt% stannous octoate core, 40wt% polyurethane shell, average particle size 15μm), 1.8 parts of polyether-modified silicone oil (HLB value 6, surface tension 22mN / m), 1 part of water, 3 parts of KH-560 modified nano silica (average particle size 50nm, surface hydroxyl content 0.1wt%); after mixing all raw materials, stir at a constant temperature for 40min at a speed of 80r / min, and store at 32℃ for later use; The second component was prepared as follows: 150 parts of polycarbonate polyol prepolymer modified isocyanate (NCO content 31%, viscosity 220 mPa·s / 25℃), which was degassed under vacuum for 18 min after prepolymer modification, with a vacuum degree of -0.085 MPa, and stored at 12℃ for later use. Step S32: Preheat the first component to 38°C and the second component to 16°C, and inject them together into the foaming mold. The temperature of the mold cavity wall is 30°C and the temperature of the middle part is 24°C. During the foaming stage, the pressure is 103 kPa, and then mixed at 15 MPa for 12 seconds. During the filling stage, the pressure is reduced to 85 kPa within 3 seconds, and then reduced to 70 kPa within 5 seconds, and held for 15 seconds. After filling, the pressure is maintained at 70 kPa for 40 seconds to cure, and then restored to 103 kPa for 2.6 minutes to cure. The material is then demolded for 3 minutes to obtain the composite foam material.

[0137] Example 3 Step S41: Preparation of the first component: by weight: 100 parts of combined polyether (70 parts of polyether polyol, 20 parts of polyester polyol, 10 parts of aromatic polyether polyol, functionality 3), 8 parts of ternary synergistic foaming agent (75wt% cyclopentane, 18wt% isobutane, 5wt% 2-methylpentane, 2wt% HFO-1233zd), 0.8 parts of microencapsulation catalyst (40wt% N,N-dimethylbenzylamine and 20wt% bismuth isooctanoate core, 40wt% polyamide shell, average particle size 5μm), 1.2 parts of polyether-modified silicone oil (HLB value 4, surface tension 25mN / m), 0.6 parts of water, 1 part of KH-570 modified nano talc powder (average particle size 100nm, surface hydroxyl content 0.3wt%); after mixing all raw materials, stir at a constant temperature for 30min at a speed of 60r / min, and store at 28℃ for later use; The second component was prepared as follows: 130 parts of polycarbonate polyol prepolymer modified isocyanate (NCO content 28%, viscosity 180 mPa·s / 25℃), which was degassed under vacuum for 15 min after prepolymer modification, with a vacuum degree of -0.08 MPa, and stored at 8℃ for later use. Step S42: Preheat the first component to 35°C and the second component to 16°C, and inject them together into the foaming mold. The mold cavity wall temperature is 28°C and the middle temperature is 22°C. During the foaming stage, the pressure is 101 kPa, and then mixed at 12 MPa for 8 seconds. During the filling stage, the pressure is reduced to 85 kPa within 3 seconds, and then reduced to 65 kPa within 5 seconds, and held for 10 seconds. After filling, the pressure is maintained at 65 kPa for 30 seconds to cure, and then restored to 101 kPa for 3 minutes to cure. The material is then demolded for 3.5 minutes to obtain the composite foam material.

[0138] Example 4 This embodiment provides a composite foaming material, and the preparation method of the composite foaming material is as follows: Step S51: Preparation of the first component: by weight: 100 parts of combined polyether (68 parts of polyether polyol, 22 parts of polyester polyol, 10 parts of aromatic polyether polyol, functionality 2.7), 10 parts of ternary synergistic foaming agent (70wt% cyclopentane, 22wt% isobutane, 7wt% 2-methylpentane, 1wt% HFO-1233zd), 1.2 parts of microencapsulation catalyst (42wt% dimethylcyclohexylamine and 18wt% dibutyltin dilaurate core, 40wt% polyurea shell, average particle size 12μm), 1.4 parts of polyether modified silicone oil (HLB value 5, surface tension 24mN / m), 0.7 parts of water, and 1.5 parts of KH-550 modified nano calcium carbonate (average particle size 70nm, surface hydroxyl content 0.25wt%). After mixing all raw materials, stir at a constant temperature for 32min at a speed of 65r / min, and store at 31℃ for later use. The second component was prepared as follows: 135 parts of polycarbonate polyol prepolymer modified isocyanate (NCO content 29%, viscosity 190 mPa·s / 25℃), which was degassed under vacuum for 16 min after prepolymer modification, with a vacuum degree of -0.082 MPa, and stored at 9℃ for later use. Step S52: Preheat the first component to 37°C and the second component to 16°C, and inject them together into the foaming mold. The mold cavity wall temperature is 29°C and the middle temperature is 23°C. During the foaming stage, the pressure is 102 kPa, and then mixed at 14 MPa for 9 seconds. During the filling stage, the pressure is reduced to 85 kPa within 3 seconds, and then reduced to 67 kPa within 5 seconds, and held for 12 seconds. After filling, the pressure is maintained at 67 kPa for 33 seconds to cure, and then restored to 102 kPa for 2.9 minutes to cure. The material is then demolded for 3.3 minutes to obtain the composite foam material.

[0139] Example 5 This embodiment provides a composite foaming material, and the preparation method of the composite foaming material is as follows: Step S61: Preparation of the first component: by weight: 100 parts of combined polyether (65 parts of polyether polyol, 24 parts of polyester polyol, 10 parts of aromatic polyether polyol, functionality 2.8), 13 parts of ternary synergistic foaming agent (68wt% cyclopentane, 23wt% isobutane, 7wt% 2-methylpentane, 2wt% HFO-1233zd), 1.1 parts of microencapsulation catalyst (46wt% dimethylcyclohexylamine and 14wt% dibutyltin dilaurate core, 40wt% polyurea shell, average particle size 8μm), 1.6 parts of polyether modified silicone oil (HLB value 5, surface tension 23mN / m), 0.9 parts of water, 2.5 parts of KH-550 modified nano calcium carbonate (average particle size 60nm, surface hydroxyl content 0.15wt%); after mixing all raw materials, stir at a constant temperature for 36min at a speed of 75r / min, and store at 29℃ for later use; The second component was prepared as follows: 145 parts of polycarbonate polyol prepolymer modified isocyanate (NCO content 30%, viscosity 210 mPa·s / 25℃), which was degassed under vacuum for 17 min after prepolymer modification, with a vacuum degree of -0.086 MPa, and stored at 11℃ for later use. Step S62: Preheat the first component to 36°C and the second component to 16°C, and inject them together into the foaming mold. The mold cavity wall temperature is 29°C and the middle temperature is 24°C. During the foaming stage, the pressure is 102 kPa, and then mixed at 13.5 MPa for 11 seconds. During the filling stage, the pressure is reduced to 85 kPa within 3 seconds, and then reduced to 69 kPa within 5 seconds, and held for 14 seconds. After filling, the pressure is maintained at 68 kPa for 36 seconds to cure, and then restored to 102 kPa for 2.7 minutes to cure. The material is then demolded for 3.1 minutes to obtain the composite foam material.

[0140] Comparative Example 1 This comparative example provides a composite foaming material, and the preparation method of the composite foaming material is as follows: First component: 100 parts of combined polyether (same as in Example 1), 12 parts of binary foaming agent (80 wt% cyclopentane, 20 wt% isobutane), 1.0 part of dimethylcyclohexylamine catalyst, 1.5 parts of ordinary silicone oil, and 0.8 parts of water; Second component: 140 parts of ordinary isocyanate (NCO content 29%).

[0141] Process parameters: The entire process is carried out under normal pressure; the storage temperature of the first and second components is 25℃; no preheating is required before mixing; the injection pressure is 13MPa; the mixing time is 10s; the mold temperature is 25℃; and the curing and demolding time is 5.5min.

[0142] Comparative Example 2 This comparative example provides a composite foaming material, and the preparation method of the composite foaming material is as follows: First component: 100 parts of polyether (same as in Example 1), 12 parts of ternary foaming agent (70 wt% cyclopentane, 25 wt% isobutane, 5 wt% HFO-1233zd), 1.0 part of dibutyltin dilaurate catalyst, 1.5 parts of ordinary silicone oil, and 0.8 parts of water; Second component: 140 parts of ordinary isocyanate (NCO content 29%).

[0143] Process parameters: negative pressure throughout the process is 70 kPa; storage temperature of the first and second components is 25℃; mixing and preheating to a temperature difference of 18℃; foaming pressure is 13 MPa; mixing time is 10 s; mold temperature is 25℃; curing and demolding time is 4.8 min.

[0144] Comparative Example 3 This comparative example provides a composite foaming material, and the preparation method of the composite foaming material is as follows: First component: 100 parts of combined polyether (same as in Example 1), 12 parts of binary foaming agent (75 wt% cyclopentane, 25 wt% dimethyl ether), 0.5 parts of dibutyltin dilaurate catalyst, 0.5 parts of dimethylcyclohexylamine catalyst, 1.5 parts of ordinary silicone oil, and 0.8 parts of water; Second component: 140 parts of ordinary isocyanate (NCO content 29%).

[0145] Process parameters: The entire process is carried out under normal pressure; the storage temperature of the first component is 30℃, the storage temperature of the second component is 10℃, and no preheating is required before mixing; the injection pressure is 13MPa, the mixing time is 10s; the mold temperature is 25℃; and the curing and demolding time is 5.2min.

[0146] The foam density, thermal conductivity, compressive strength, flow distance, low-temperature deformation rate, and closed-cell rate of the composite foamed materials in Examples 1-5 and Comparative Examples 1-3 were tested. The test results are shown in Table 1.

[0147] The foam density was tested in accordance with the GB / T 6343-2009 standard: the mass of the sample was weighed, the volume was measured, and the mass-to-volume ratio was calculated.

[0148] The thermal conductivity was tested in accordance with GB / T 10294-2008 standard "Determination of Steady-State Thermal Resistance and Related Properties of Insulation Materials - Protective Hot Plate Method".

[0149] The compressive strength was tested in accordance with GB / T 8813-2022 standard "Determination of compressive properties of rigid foamed plastics".

[0150] The flow distance was measured using a measuring tape.

[0151] The low-temperature deformation rate was tested in accordance with GB / T 8811-2008 / ISO 2796:1986 standard "Test method for dimensional stability of rigid foamed plastics". The calculation formula is: (dimensionality after cycle - dimensionality before cycle) / dimensionality before cycle × 100%.

[0152] The closed-cell rate was tested according to GB / T 10799-2008 standard "Determination of open-cell and closed-cell volume percentage of rigid foamed plastics".

[0153] Table 1

[0154] From Table 1, we can obtain: The foam densities of Examples 1-5 are all ≤31kg / m³, which is 5-7kg / m³ lower than the comparative example, demonstrating the low-density advantage of the ternary foaming system. The thermal conductivity of Examples 1-5 is all ≤18.8mW / (m·K), meeting the new energy efficiency standards, which is 1.4-3.3mW / (m·K) lower than the comparative example. This is attributed to the nucleation effect of HFO-1233zd and the refinement of the foam cells by gradient negative pressure. The flow distance of Examples 1-5 is all ≥358mm, which is 25-82mm higher than the comparative example, meeting the filling requirements of ultra-thin refrigerators (cavity width ≤35mm). The core reason is the guiding effect of 2-methylpentane in reducing the viscosity of the system and the temperature control of the partitioned mold. The demolding time of Examples 1-5 is all ≤3.5min, which is 1.7-2.5min shorter than the comparative example, and the production efficiency is increased by more than 40%. This is due to the "on-demand catalysis" of the microencapsulated composite catalyst and the accelerated curing by gradient negative pressure.

[0155] The method for preparing composite foamed materials provided in this application solves the compatibility problem of ternary components: the compatibility of 2-methylpentane with cyclopentane and isobutane is precisely controlled, and the problem of easy escape of isobutane is solved by dynamic temperature-controlled storage; a balance between catalytic efficiency and storage stability is achieved: the thickness of the microcapsule shell and the rupture pressure need to be matched with the production process to avoid failure during storage or insufficient release during mixing; the quality of the foam is improved by optimizing the gradient negative pressure parameter to avoid foaming agent loss and foam rupture; and the multi-performance coupling synergy solves the contradiction between low density and high strength, high flow and low thermal conductivity, and achieves a balance through the integrated design of components and processes.

[0156] The technical solutions provided by the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A composition, characterized in that, Includes the first component and the second component; The first component includes a polyether, a foaming agent, and a microencapsulated catalyst. The microencapsulated catalyst includes a core and a shell covering the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers. The second component includes isocyanate.

2. The composition according to claim 1, characterized in that, The average particle size of the microencapsulated catalyst is 5 μm to 20 μm; The average particle size of the kernel is 3μm~16μm; The average thickness of the shell is 1μm~2μm; The amine catalyst includes one or more of dimethylcyclohexylamine, triethylenediamine, and N,N-dimethylbenzylamine; The metal catalyst includes one or more of dibutyltin dilaurate, stannous octoate, and bismuth isooctanoate. The polymer includes one or more of polyurea, polyamide, and polyurethane; In the microencapsulated catalyst, the mass ratio of the amine catalyst, the metal catalyst and the polymer is (40~50):(10~20):(30~50).

3. The composition according to claim 1, characterized in that, The functionality of the polyether composition is 2.5 to 3; The combined polyether includes one or more of polyether polyols, polyester polyols, and aromatic polyether polyols; The foaming agent includes cyclopentane, isobutane, and 2-methylpentane; The foaming agent also includes an auxiliary nucleating agent; the auxiliary nucleating agent includes HFO-1233zd; In the foaming agent, the mass ratio of cyclopentane, isobutane, 2-methylpentane and the auxiliary nucleating agent is (60~80):(15~25):(3~8):(0.5~1.5).

4. The composition according to claim 1, characterized in that, The first component also includes a nano-reinforcing agent; The first component also includes silicone oil; The first component also includes water.

5. The composition according to claim 4, characterized in that, It also includes at least one of the following features (1) to (2): (1) The surface hydroxyl content of the nano-reinforcing agent is less than or equal to 0.3 wt%; The nano-reinforcing agent includes silane coupling agent modified nanomaterials; the average particle size of the nanomaterials is 50 nm to 100 nm; The silane coupling agent includes one or more of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; The nanomaterials include one or more of calcium carbonate, talc, and silicon dioxide. (2) The HLB value of the silicone oil is 4~6; The surface tension of the silicone oil is 20mN / m~25mN / m; The silicone oil includes one or more of polyether-modified silicone oil and fluorine-modified silicone oil.

6. The composition according to claim 4 or 5, characterized in that, By weight, the first component comprises: 100 parts of the combined polyether, 8-15 parts of the foaming agent, 0.8-1.5 parts of the microencapsulation catalyst, 1-3 parts of the nano-reinforcing agent, 1.2-1.8 parts of the silicone oil, and 0.6-1 parts of the water; The isocyanate has an NCO content of 28% to 32%; The viscosity of the isocyanate is 180 mPa·s to 220 mPa·s; The isocyanate includes polycarbonate polyol modified isocyanate; The mass ratio of the polyether to the isocyanate is 100:(130~150).

7. A method for preparing a composite foamed material, characterized in that, Includes the following steps: Provide the first component and the second component; The first component and the second component are subjected to a foaming treatment to obtain a composite foam material; The first component includes a polyether, a foaming agent, and a microencapsulated catalyst. The microencapsulated catalyst includes a core and a shell covering the core. The core is made of amine catalysts and metal catalysts, and the shell is made of polymers. The second component includes isocyanate.

8. The preparation method according to claim 7, characterized in that, The storage temperature of the first component is 28℃~32℃; The storage temperature for the second component is 8℃~12℃; Before mixing the first component and the second component, the method further includes: preheating the first component to a first temperature and preheating the second component to a second temperature; wherein the temperature difference between the first temperature and the second temperature is 18℃~23℃, the first temperature is 35℃~40℃, and the second temperature is 15℃~20℃.

9. The preparation method according to claim 7, characterized in that, The foaming process includes a foam injection stage, a filling stage, and a curing stage performed sequentially within the mold; wherein... The foaming stage includes: injecting the first component and the second component, and mixing the first component and the second component; wherein the pressure of injecting the first component and the second component is 101 kPa to 103 kPa, the pressure of mixing the first component and the second component is 10 MPa to 15 MPa, and the time of mixing the first component and the second component is 8 s to 12 s; The filling stage includes: reducing the pressure to a first pressure in a first time period, reducing the pressure to a second pressure in a second time period, and holding the pressure for a third time period; wherein, the first time period is 1s~3s, the first pressure is 82kPa~88kPa, the second time period is 4s~6s, the second pressure is 65kPa~70kPa, and the third time period is 10s~15s; The curing stage includes: holding pressure at a third pressure for a fourth time period, and holding pressure at a fourth pressure for a fifth time period; wherein the third pressure is 65kPa~70kPa, the fourth time period is 30s~40s, the fourth pressure is 101kPa~103kPa, and the fifth time period is 2.5min~3min. The temperature of the cavity wall of the mold is greater than the temperature of the middle part of the mold; wherein the temperature of the cavity wall of the mold is 28℃~30℃, and the temperature of the middle part of the mold is 22℃~25℃.

10. A composite foaming material, characterized in that, It is prepared by the preparation method according to any one of claims 7 to 9.

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