A preparation method of phase-change flame-retardant polyurethane foam

Abstract

The invention relates to a preparation method of a phase-change flame-retardant polyurethane foam, which specifically comprises the following steps: phosphorus oxychloride and vanillin are dissolved in a solvent and reacted under the catalysis of an alkali catalyst to obtain an intermediate A; the intermediate A and polyetheramine or polyethylene glycol diamine are dissolved in a solvent and subjected to an addition reaction to obtain a flame-retardant polyetheramine; polyethylene glycol and the flame-retardant polyetheramine are added to the raw materials for preparing the polyurethane foam, so that the polyurethane foam has phase-change heat storage and heat release functions, thereby realizing heat regulation within a certain temperature range; since the flame-retardant polyetheramine contains a large amount of nitrogen and phosphorus elements in its structure, it has excellent biological nitrogen-phosphorus synergistic flame-retardant performance, thereby effectively improving the flame retardancy and stability of the polyurethane foam; in addition, the polyurethane foam also exhibits good mechanical strength; and the use comfort of the soft polyurethane foam is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane foam, and in particular to a method for preparing phase-change flame-retardant polyurethane foam. Background Art

[0002] Soft polyurethane foam is often used for car interior and home decoration because of its low density, good wrapping and good cushioning and damping effect. In recent years, due to the rise of new energy vehicles and people's increasing requirements for quality of life, the demand for soft polyurethane foam is also increasing.

[0003] Common soft polyurethane foam contains a large number of flammable hydrocarbon segments, and due to its low density and porous structure, its oxygen index is only 14-18%, showing high flammability. When it is used in automotive interiors and home decoration, it must be flame-retardant treated. There are two common methods for improving the flame retardant properties of soft polyurethane foam: one is to add flame retardants, such as dimethyl methylphosphonate, triethyl phosphate, tri(2-chloroisopropyl) phosphate (Chinese patent CN114854002B), melamine, aluminum hydroxide, etc., but there are problems such as low flame retardant efficiency, poor dispersibility and compatibility, easy migration and dissolution, and deterioration of the mechanical properties of the substrate; the other is to add reactive flame retardants, and introduce nitrogen, phosphorus (Chinese patent CN117229315A, Chinese patent CN116675825A), halogen (Chinese patent CN117534828A) and other elements into the molecular structure of polyurethane foam through chemical bonds, which has permanent flame retardant properties, but the introduction of halogens has certain biocompatibility and environmental problems.

[0004] On the other hand, when soft polyurethane foam is used in car interiors and home decoration, self-regulation of human body temperature comfort is particularly important, especially in summer and winter.

[0005] It is of great significance to use phase change materials with heat storage function to modify rigid polyurethane foam and prepare composite materials with excellent temperature control ability; phase change flame retardant polyurethane foam: refers to flame retardant polyurethane foam with self-regulating temperature; therefore, how to make soft polyurethane foam realize both temperature self-regulation and flame retardant functions through molecular design is of great significance to further improve the comfort and safety of soft polyurethane foam. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing a phase-change flame-retardant polyurethane foam, so as to solve the problem that the soft polyurethane foam currently on the market does not have both the temperature self-regulation and flame-retardant functions.

[0007] In order to solve the above technical problems, the technical solution of the present invention is: a method for preparing a phase-change flame-retardant polyurethane foam, characterized in that: the phase-change flame-retardant polyurethane foam comprises the following raw materials: polyether polyol, polyethylene glycol, flame-retardant polyether amine, foam stabilizer, reactive composite catalyst, water and isocyanate; The amount of polyether polyol used is 60 to 90 parts; The molecular weight of polyethylene glycol is 2000-4000, and the dosage is 10-30 parts; Flame retardant polyetheramine, dosage is 10 to 30 parts; The amount of foam stabilizer is 0.05-4.0 parts, the amount of reactive composite catalyst is 0.05-2.0 parts, the amount of water is 1.0-5.0 parts, and the amount of isocyanate is 40-80 parts; The specific foaming method is: the above raw materials are made into polymer raw materials, the raw materials are pumped into the foaming machine through a pipeline, and the head of the foaming machine performs open continuous low-pressure flat foaming, and the polymerized material is sprayed onto the landing board of the foaming machine through the foaming nozzle of the foaming machine. The flow rate of the material sprayed by the foaming nozzle is controlled at 60-500 kg / min, and a conveyor belt is arranged on the rear side of the landing board. Kraft paper is also laid on the landing board. The foaming nozzle sprays the sponge onto the kraft paper, and the kraft paper moves forward with the conveyor belt at a speed of 1-8 m / min, thereby driving the sponge to move forward together, realizing foaming and conveying at the same time; wherein, the molecular structure of the flame-retardant polyetheramine is as follows: or Further, the specific preparation method is as follows: S1: Phosphorus oxychloride and vanillin are dissolved in a solvent and reacted under the catalysis of an alkali catalyst to obtain an intermediate A; wherein the stoichiometric ratio of phosphorus oxychloride, vanillin and alkali catalyst is 1.0:3.1-4.0:3.0-5.0; the reaction temperature is 0-60°C, and the reaction time is 6-12h; S2: intermediate A and polyetheramine or polyethylene glycol diamine are dissolved in a solvent to undergo an addition reaction to obtain a flame retardant polyetheramine; the stoichiometric ratio of intermediate A to polyethylene glycol diamine is 2.0:3.1-4.0; the molecular weight of polyetheramine is 400-2000, and the molecular weight of polyethylene glycol diamine is 400-2000; the temperature of the addition reaction is 50-80°C, and the reaction time is 12-48h.

[0008] Furthermore, the base catalyst is selected from one or more of triethylamine, pyridine, sodium acetate, sodium carbonate, and potassium carbonate.

[0009] Furthermore, the solvents in S1 and S2 are both selected from one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and chloroform.

[0010] Furthermore, the foam stabilizer is an organosilicon foam stabilizer or a polysiloxane-polyoxyalkylene mosaic copolymer.

[0011] Furthermore, the reactive composite catalyst is one or a combination of tin catalyst and amine catalyst.

[0012] The advantages of the present invention are: 1) In the present invention, polyethylene glycol and flame-retardant polyetheramine are added to the raw materials for preparing polyurethane foam, so that the polyurethane foam has phase change heat storage and heat release functions, thereby realizing thermal regulation within a certain temperature range; since the flame-retardant polyetheramine structure contains a large amount of nitrogen and phosphorus elements, it has excellent biological nitrogen-phosphorus synergistic flame retardant properties, thereby effectively improving the flame retardancy and stability of the polyurethane foam; in addition, this type of polyurethane foam also exhibits good mechanical strength, further improving the comfort of use of the soft polyurethane foam. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown herein can be arranged and designed in various different configurations.

[0014] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Embodiment 1: Vanillin and triethylamine were dissolved in chloroform, the temperature of the reaction system was controlled to be 0°C, phosphorus oxychloride was added dropwise under mechanical stirring, the temperature was kept at 0°C for 2 hours, and then the temperature was raised to 50°C for further reaction for 8 hours, and the molar ratio of phosphorus oxychloride, vanillin and triethylamine was controlled to be 1.0:3.3:3.3; after the reaction was completed, the mixture was poured into excess petroleum ether, and intermediate A was obtained after precipitation, filtration and washing; The intermediate A and polyetheramine (Mn=~400) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2, reacted at 50°C for 2 hours, then heated to 70°C and continued to react for 2 hours. After vacuum drying, a flame-retardant polyetheramine was obtained, the molecular formula of which is shown below: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0016] Embodiment 2: Dissolve vanillin and triethylamine in chloroform and control the temperature of the reaction system to 0 o C, add phosphorus oxychloride dropwise under mechanical stirring, and react at this temperature for 2h, then raise the temperature to 50 o C, continue the reaction for 8 hours, the molar ratio of phosphorus oxychloride, vanillin and triethylamine is 1.0:3.3:3.3; after the reaction is completed, pour the mixture into excess petroleum ether, precipitate, filter and wash to obtain intermediate A; The intermediate A and polyetheramine (Mn = ~1000) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2. o After reacting for 2 h at 70 o C continues to react for 2 hours, and after vacuum drying, a flame-retardant polyether amine is obtained, and its molecular formula is as follows: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0017] Embodiment 3: Dissolve vanillin and triethylamine in chloroform and control the temperature of the reaction system to 0 o C, add phosphorus oxychloride dropwise under mechanical stirring, and react at this temperature for 2h, then raise the temperature to 50 o C, continue the reaction for 8 hours, the molar ratio of phosphorus oxychloride, vanillin and triethylamine is 1.0:3.3:3.3; after the reaction is completed, pour the mixture into excess petroleum ether, precipitate, filter and wash to obtain intermediate A; The intermediate A and polyetheramine (Mn = ~2000) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2. o After reacting for 2 h at 70 o C continues to react for 2 hours, and after vacuum drying, a flame-retardant polyether amine is obtained, and its molecular formula is as follows: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0018] Embodiment 4: Dissolve vanillin and triethylamine in chloroform and control the temperature of the reaction system to 0 o C, add phosphorus oxychloride dropwise under mechanical stirring, and react at this temperature for 2h, then raise the temperature to 50 o C, continue the reaction for 8 hours, the molar ratio of phosphorus oxychloride, vanillin and triethylamine is 1.0:3.3:3.3; after the reaction is completed, pour the mixture into excess petroleum ether, precipitate, filter and wash to obtain intermediate A; The intermediate A and polyethylene glycol diamine (Mn = ~400) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2. o After reacting for 2 h at 70 o C continues to react for 2 hours, and after vacuum drying, a flame-retardant polyether amine is obtained, and its molecular formula is as follows: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0019] Embodiment 5: Dissolve vanillin and triethylamine in chloroform and control the temperature of the reaction system to 0 o C, add phosphorus oxychloride dropwise under mechanical stirring, and react at this temperature for 2h, then raise the temperature to 50 o C, continue the reaction for 8 hours, the molar ratio of phosphorus oxychloride, vanillin and triethylamine is 1.0:3.3:3.3; after the reaction is completed, pour the mixture into excess petroleum ether, precipitate, filter and wash to obtain intermediate A; The intermediate A and polyethylene glycol diamine (Mn = ~1000) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2. o After reacting for 2 h at 70 o C continues to react for 2 hours, and after vacuum drying, a flame-retardant polyether amine is obtained, and its molecular formula is as follows: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0020] Embodiment 6: Dissolve vanillin and triethylamine in chloroform and control the temperature of the reaction system to 0 o C, add phosphorus oxychloride dropwise under mechanical stirring, and react at this temperature for 2h, then raise the temperature to 50 o C, continue the reaction for 8 hours, the molar ratio of phosphorus oxychloride, vanillin and triethylamine is 1.0:3.3:3.3; after the reaction is completed, pour the mixture into excess petroleum ether, precipitate, filter and wash to obtain intermediate A; The intermediate A and polyethylene glycol diamine (Mn = ~2000) were dissolved in chloroform at a stoichiometric ratio of 2.0:3.2. o After reacting for 2 h at 70 o C continues to react for 2 hours, and after vacuum drying, a flame-retardant polyether amine is obtained, and its molecular formula is as follows: The phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of polyether with a molecular weight of 3000 and a hydroxyl value of 56, 25 parts of polyethylene glycol with a molecular weight of 2000, 20 parts of flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of organosilicon foam stabilizer, 0.5 parts of amine catalyst, and 2.6 parts of water.

[0021] The polyurethane foams in Examples 1 to 6 are all made by the following method: the raw materials are pumped into a foaming machine through a pipeline, and an open continuous low-pressure flat foaming is performed by the foaming machine head. The polymerized material is sprayed onto a landing plate of the foaming machine through a foaming nozzle of the foaming machine. The flow rate of the material sprayed by the foaming nozzle is controlled at 60 to 500 kg / min. A conveyor belt is provided on the rear side of the landing plate, and kraft paper is also laid on the landing plate. The foaming nozzle sprays the sponge onto the kraft paper, and the kraft paper moves forward with the conveyor belt at a speed of 1 to 8 m / min, thereby driving the sponge to move forward together, realizing foaming and conveying at the same time.

[0022] Comparative Example 1: The difference between this comparative example and Example 1 is that the amounts of the components of the phase change flame retardant polyurethane foam are as follows: the phase change flame retardant polyurethane foam is composed of the following components in parts by weight: 65 parts of a polyether having a molecular weight of 3000 and a hydroxyl value of 56, 15 parts of polyethylene glycol having a molecular weight of 2000, 30 parts of a flame retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of an organosilicon foam stabilizer, 0.5 parts of an amine catalyst, and 2.6 parts of water.

[0023] Comparative Example 2: The difference between this comparative example and Example 1 is that the amounts of the components of the phase-change flame-retardant polyurethane foam are as follows: the phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 80 parts of a polyether having a molecular weight of 3000 and a hydroxyl value of 56, 30 parts of a flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of an organosilicon foam stabilizer, 0.5 parts of an amine catalyst, and 2.6 parts of water.

[0024] Comparative Example 3 The difference between this comparative example and Example 1 is that the amounts of the components of the phase-change flame-retardant polyurethane foam are as follows: the phase-change flame-retardant polyurethane foam is composed of the following components in parts by weight: 75 parts of a polyether having a molecular weight of 3000 and a hydroxyl value of 56, 30 parts of polyethylene glycol having a molecular weight of 2000, 5 parts of a flame-retardant polyether amine, 45 parts of toluene diisocyanate, 2 parts of an organosilicon foam stabilizer, 0.5 parts of an amine catalyst, and 2.6 parts of water.

[0025] The polyurethane foams prepared in Comparative Examples 1 to 3 were prepared in the same manner as the polyurethane foams prepared in Examples 1 to 6.

[0026] The polyurethane foams prepared in Examples 1-6 and Comparative Examples 1-3 were tested for physical properties. The test results are shown in Table 1.

[0027] Table 1 Test results of properties of polyurethane foams prepared in Examples 1 to 6 and Comparative Examples 1 to 3 Density (kg / m3) Hardness (lbs IBF) Oxygen index (%) Melting temperature (°C) Crystallization temperature (oC) Melting enthalpy (J / g) Crystallization enthalpy (J / g) Example 1 47.4 35.5 26.5 32.5 24.5 77.5 74.9 Example 2 40.4 30.6 25.7 31.7 23.7 75.3 71.3 Example 3 37.8 27.8 25.1 31.4 24.1 78.1 75.7 Example 4 45.7 34.3 25.9 33.2 25.3 80.4 80.1 Example 5 39.4 29.6 24.7 31.5 24.6 85.6 83.8 Example 6 36.3 28.8 24.5 32.1 24.7 94.8 90.5 Comparative Example 1 49.6 37.6 27.8 33.3 25.1 63.4 58.9 Comparative Example 2 50.9 40.4 28.1 — — — — Comparative Example 3 40.7 26.6 23.1 32.5 24.7 85.3 83.7 The above data fall within the scope of experimental verification and do not contradict common knowledge; Density determination method: Determine the density of polyurethane soft foam material according to GB / T6343-2009 "Determination of apparent density of foam plastics and rubber". Place the polyurethane soft foam material in the environment (dryer) specified in the standard for at least 16 hours. After reaching a stable state, measure the size of the sample according to the provisions of GB / T6342-1996. Measure at least three times and calculate the average value as the final measurement result. Finally, calculate the measured result according to ρ = (m / V) x 10 6 , calculate the apparent density of the foam. Where: ρ—apparent density, unit is kilograms per cubic meter (kg / m 3 m—mass of the sample, in grams (g); V—volume of the sample, in cubic millimeters (mm 3 ).

[0028] Hardness measurement: According to GB / T10807-2006 "Determination of hardness of soft foam polymer materials (indentation method)", the hardness of polyurethane soft foam materials is measured.

[0029] Oxygen index: The flame retardant properties of polyurethane soft foam materials are determined according to the standard GB / T 2406.2-2009 "Determination of combustion behavior of plastics by oxygen index method Part 2: Room temperature test".

[0030] The phase change value test method of the phase change flame retardant polyurethane foam of the present invention is as follows: using a differential scanning calorimeter DSC2500 of TA Company of the United States, the test temperature range is -40 to 100°C, nitrogen atmosphere, and the heating and cooling rates are both 10°C / min.

[0031] As can be seen from Table 1, compared with Examples 1 to 3, as the molecular weight of polyetheramine increases, the density and hardness of the obtained polyurethane foam are slightly reduced, but the oxygen index, melting temperature, crystallization temperature, melting enthalpy and crystallization enthalpy do not change much. Comparing Example 1 with Comparative Examples 1 to 3, it can be found that as the proportion of flame-retardant polyetheramine increases, the oxygen index of polyurethane foam density increases, and the flame retardant performance is enhanced; when the proportion of polyethylene glycol is 0, the obtained polyurethane foam does not have a phase change function, because at this time there is no linear molecular chain with a heat storage function in the foam molecular chain, that is, in the polyurethane foam, the phase change function is still the phase change material-polyethylene glycol, not the polyethylene glycol diamine in the flame-retardant polyetheramine; therefore, when the molecular weight of polyethylene glycol diamine is different, the influence on the melting temperature of polyurethane foam is limited; on the other hand, when the proportion of polyethylene glycol increases and the proportion of flame-retardant polyetheramine decreases, the melting enthalpy and crystallization enthalpy of the obtained polyurethane foam are increased. It can be seen from comparative examples 4 to 6 that when polyethylene glycol diamine replaces polyetheramine to synthesize flame-retardant polyetheramine, the melting enthalpy and crystallization enthalpy of the obtained polyurethane foam are greatly increased. This is because the molecular chain of polyethylene glycol diamine is similar to the molecular chain of polyethylene glycol, which increases the number of molecular chains that can realize phase change energy storage in the polyurethane foam, and as the molecular weight of polyethylene glycol diamine increases, the melting enthalpy and crystallization enthalpy of the obtained polyurethane foam also increase accordingly; that is, the molecular chain of polyethylene glycol diamine has a certain interaction with the molecular chain of polyethylene glycol, thereby increasing the melting enthalpy and crystallization enthalpy, and the interaction between molecules will affect the melting temperature, which cannot be considered to be contrary to the fact that the lower the molecular weight, the lower the melting temperature.

[0032] By comparing Example 1 with Example 4, it can be seen that when the molecular structure of the flame-retardant polyetheramine is linear, the molecular structure has less hindrance to the melting and crystallization of the polyethylene glycol molecular chain, which is conducive to obtaining higher melting enthalpy and crystallization enthalpy.

[0033] Those skilled in the art should understand that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, and these changes and improvements shall all fall within the scope of the present invention claimed for protection.

Claims

1. A method for preparing a phase-change flame-retardant polyurethane foam, characterized in that: The phase-change flame-retardant polyurethane foam comprises the following raw materials: polyether polyol, polyethylene glycol, flame-retardant polyether amine, foam stabilizer, reactive composite catalyst, water and isocyanate; The amount of polyether polyol used is 60 to 90 parts; The molecular weight of polyethylene glycol is 2000-4000, and the dosage is 10-30 parts; Flame retardant polyetheramine, dosage is 10 to 30 parts; The amount of foam stabilizer is 0.05-4.0 parts, the amount of reactive composite catalyst is 0.05-2.0 parts, the amount of water is 1.0-5.0 parts, and the amount of isocyanate is 40-80 parts; The specific foaming method is: the above raw materials are made into polymer raw materials, the raw materials are pumped into the foaming machine through a pipeline, and the head of the foaming machine performs open continuous low-pressure flat foaming, and the polymerized materials are sprayed onto the landing board of the foaming machine through the foaming nozzle of the foaming machine. The flow rate of the material sprayed by the foaming nozzle is controlled at 60-500 kg / min, and a conveyor belt is arranged on the rear side of the landing board. Kraft paper is also laid on the landing board. The foaming nozzle sprays the sponge onto the kraft paper, and the kraft paper moves forward with the conveyor belt at a speed of 1-8 m / min, thereby driving the sponge to move forward together, realizing foaming and conveying at the same time; wherein, the molecular structure of the flame-retardant polyetheramine is as follows: or 。 2. The method for preparing a phase change flame retardant polyurethane foam according to claim 1, characterized in that: The specific preparation method is as follows: S1: Phosphorus oxychloride and vanillin are dissolved in a solvent and reacted under the catalysis of an alkali catalyst to obtain an intermediate A; wherein the stoichiometric ratio of phosphorus oxychloride, vanillin and alkali catalyst is 1.0:3.1-4.0:3.0-5.0; the reaction temperature is 0-60°C, and the reaction time is 6-12h; S2: intermediate A and polyetheramine or polyethylene glycol diamine are dissolved in a solvent to undergo an addition reaction to obtain a flame retardant polyetheramine; the stoichiometric ratio of intermediate A to polyethylene glycol diamine is 2.0:3.1-4.0; the molecular weight of polyetheramine is 400-2000, and the molecular weight of polyethylene glycol diamine is 400-2000; the temperature of the addition reaction is 50-80°C, and the reaction time is 12-48h.

3. The method for preparing a phase change flame retardant polyurethane foam according to claim 2, characterized in that: The base catalyst is selected from one or more of triethylamine, pyridine, sodium acetate, sodium carbonate and potassium carbonate.

4. The method for preparing a phase change flame retardant polyurethane foam according to claim 2, characterized in that: The solvents in S1 and S2 are both selected from one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and chloroform.

5. The method for preparing a phase change flame retardant polyurethane foam according to claim 1, characterized in that: The foam stabilizer is an organic silicon foam stabilizer or a polysiloxane-polyoxyalkylene mosaic copolymer.

6. The method for preparing a phase change flame retardant polyurethane foam according to claim 1, characterized in that: The reactive composite catalyst is one of a tin catalyst and an amine catalyst or a combination of both.

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