CN117186346A - Flame-retardant polyurethane foam material and preparation method thereof - Google Patents

Abstract

The application belongs to the technical field of flame retardant materials, and relates to a flame retardant polyurethane foam material and a preparation method thereof. The raw materials comprise: polyether polyol component, isocyanate component, phase change material and composite flame retardant, wherein the composite flame retardant is prepared by intercalation compounding of modified magnesium aluminum hydrotalcite and nitrogen-phosphorus flame retardant. The phase change material can reduce the highest reaction temperature of the polyurethane foam reaction system, and the composite flame retardant can greatly improve the flame retardance of the polyurethane foam material. Meanwhile, the intercalation compounding of the modified magnesium aluminum hydrotalcite and the nitrogen-phosphorus flame retardant greatly improves the dispersion state of the modified magnesium aluminum hydrotalcite and the nitrogen-phosphorus flame retardant in the polyurethane foam material matrix, so that the synthesized polyurethane foam material has more uniform pore size distribution and improved mechanical property while the flame retardant property is improved.

Description

Flame-retardant polyurethane foam material and preparation method thereof

Technical Field

The application belongs to the technical field of flame retardant materials, and particularly relates to a flame retardant polyurethane foam material and a preparation method thereof.

Background

Polyurethane foams have many advantages for plugging mines: the adhesive property with the coal body is strong in the reaction process, and the foam stability after solidification is good; the bubbles are of a closed pore structure, so that the problems of cracking, falling and the like are not easy to occur; the filling capability of the pore is strong, the sealing effect is good, and the air migration can be effectively prevented; the hydraulic shock absorber has certain compression strength, can bear stratum movement, and is shock-proof and compression-resistant. The advantages enable the polyurethane foam material to be widely popularized and used in coal mine sites.

However, the isocyanate and polyether polyol which are reaction raw materials of polyurethane release a large amount of heat in the foaming process, and the polyurethane foam material has poor heat conductivity and is extremely easy to burn, toxic smog can be generated in the combustion process, even the oxidation process of coal is accelerated, and certain conditions are provided for mine fire. When the mine is used for reinforcing the fault fracture zone, a large amount of polyurethane foam materials are used, the contact area of polyurethane and coal is large, spontaneous combustion of coal can be promoted by heat released in the reaction process, polyurethane combustion further occurs, coal ignition is caused, a large amount of toxic and harmful gases such as CO are released, and huge loss is brought to the coal mine. Therefore, the problems of large reaction heat release, poor flame retardant property and the like of the polyurethane foam in the using process are solved, and the polyurethane foam has important significance in guaranteeing the safe use of the polyurethane in coal mines.

The highest reaction temperature is an important index for judging the exothermic condition of the polyurethane foam material, and students at home and abroad can reduce the highest reaction temperature of the polyurethane according to different cooling mechanisms. The Shen J and the like reduce the highest reaction temperature of the polyurethane foam material to below 120 ℃ by adjusting the proportion of the polyurethane foam raw materials, and research the foaming process and the mechanical property of the polyurethane foam material; dong Jun and the like utilize a chemical reaction endothermic method to add a modifier into a matrix to react with the modifier to absorb heat, the reaction process of the polyurethane foam material matrix is controlled, and when the addition amount of the modifier is 2%, the highest reaction temperature is 112 ℃ at the lowest; wu Huaiguo the comparison of polyurethane foams with the addition of water and silicate, respectively, shows that silicate can lower the maximum reaction temperature of polyurethane, while the addition of water allows the maximum reaction temperature to be about twice that of unmodified polyurethane; liu Yuting inert gas is added as a modifier to the polyurethane, when the addition amount is 20phr, the highest reaction temperature is reduced from 137 ℃ to 85 ℃, but the time required for curing the foam is increased, and the mechanical property is reduced; yang Shuai the highest reaction temperature of polyurethane is reduced to about 107 ℃ by adding the modifier, but the mechanical property is reduced due to the thinning of the pore wall.

In the prior art, the problem of high heat release of the polyurethane foam material can be solved by different modes, but the cost can be greatly increased, and other performances are weakened, especially the mechanical properties such as compression strength and the like can be caused, so that the use of the polyurethane foam material is influenced, and the finding of a new cooling method has important significance.

Disclosure of Invention

The application aims to provide a flame-retardant polyurethane foam material and a preparation method thereof, which are used for solving the problems in the prior art.

In order to achieve the above purpose, the present application provides the following technical solutions:

one of the technical schemes of the application is as follows: the flame-retardant polyurethane foam material comprises the following components in parts by mass:

57 parts of polyether polyol component, 43 parts of isocyanate component, 3-8 parts of phase change material and 20 parts of composite flame retardant.

Further, the flame-retardant polyurethane foam material comprises the following components in parts by mass:

57 parts of polyether polyol component, 43 parts of isocyanate component, 5 parts of phase change material and 20 parts of composite flame retardant.

Further, the polyether polyol component and the isocyanate component are commercially available products available from Shanghai Guangdong building materials Co.

Further, the phase change material includes one of lauric acid, capric acid, palmitic acid, caprylic acid, n-octadecane and n-eicosane.

Preferably, the phase change material is palmitic acid.

It is worth to say that, in the application, in order to reduce the highest reaction temperature, the phase change material is added, after the phase change temperature is reached, the phase change energy storage effect is utilized to absorb the heat generated in the polyurethane matrix reaction process, the process is isothermal or nearly isothermal, namely, the heat absorption and melting are carried out when the system is heated in the early stage of reaction, part of energy is stored, the temperature can be continuously increased only after the storage is completed, and the effect of reducing the highest reaction temperature is achieved. After the reaction is completed, no heat is generated, and the temperature of the material is reduced due to heat transfer with air, so that the phase change material can release heat, and a more stable cell structure is formed. In the whole process, the volume of the phase change material is changed less, and the phenomenon of shrinkage after foam molding can not occur.

Further, the composite flame retardant is prepared by intercalation compounding of modified magnesium aluminum hydrotalcite (modified LDHs) and nitrogen-phosphorus flame retardants.

Preferably, the mass ratio of the modified magnesium aluminum hydrotalcite to the nitrogen-phosphorus flame retardant is 1-19:1-19.

Preferably, the intercalation compounding method comprises the following steps: and mixing and grinding the modified magnesium aluminum hydrotalcite and the nitrogen-phosphorus flame retardant for 30min to complete the intercalation compounding.

Preferably, the nitrogen-phosphorus flame retardant is ammonium polyphosphate (APP) or melamine phosphate (MPP).

Preferably, the modified magnesium aluminum hydrotalcite is obtained by surface modification of magnesium aluminum hydrotalcite by a silane coupling agent.

Preferably, the silane coupling agent includes one of gamma-glycidoxypropyl trimethylsilane (KH 560), gamma-aminopropyl triethoxysilane (KH 550), and gamma- (methacryloyloxy) propyl trimethoxysilane (KH 570).

Preferably, the surface modification step is as follows:

adding water into the magnesium aluminum hydrotalcite to prepare hydrotalcite slurry;

weighing a silane coupling agent according to 3-7% of the mass of the magnesium aluminum hydrotalcite, adding the silane coupling agent into absolute ethyl alcohol, and regulating the pH value to be 5 by using glacial acetic acid to obtain a silane coupling agent solution;

slowly dripping the silane coupling agent solution into the hydrotalcite slurry, stirring for 4 hours, centrifuging, and drying to finish the surface modification.

Preferably, the addition amount of the silane coupling agent is 3% of the mass of the magnesium aluminum hydrotalcite.

The second technical scheme of the application is as follows: provided is a method for preparing a flame retardant polyurethane foam material, comprising:

preparing a polyether polyol component, an isocyanate component, a phase change material and a composite flame retardant according to the mass parts;

and uniformly mixing the polyether polyol component, the phase change material and the composite flame retardant, adding the isocyanate component, uniformly stirring, and naturally foaming and curing to obtain the flame-retardant polyurethane foam material.

Further, the stirring time was 10s.

Further, the curing method comprises the following steps: after the foam is stable, the foam is left to stand for 5 minutes in a room temperature environment, and then the complete solidification is completed.

The third technical scheme of the application: the application of the flame-retardant polyurethane foam material in mines is provided.

The fourth technical scheme of the application: the method for reducing the highest reaction temperature of the flame-retardant polyurethane foam material is characterized in that a phase change material is added into raw materials of the flame-retardant polyurethane foam material, and the addition amount of the phase change material is 3-8% of the total mass of a polyether polyol component and an isocyanate component.

Further, the method for reducing the highest reaction temperature of the flame-retardant polyurethane foam material further comprises adding a composite flame retardant accounting for 5-20% of the total mass of the polyether polyol component and the isocyanate component.

The preferable composite flame retardant is prepared by intercalation compounding of modified magnesium aluminum hydrotalcite and nitrogen-phosphorus flame retardant.

Preferably, the modified magnalium hydrotalcite is obtained by carrying out surface modification on the magnalium hydrotalcite by a silane coupling agent

Compared with the prior art, the technical scheme has the following beneficial effects:

the intercalation compounding of the modified magnesium aluminum hydrotalcite and the nitrogen-phosphorus flame retardant improves the problems of poor compatibility and poor dispersibility of the modified magnesium aluminum hydrotalcite and the nitrogen-phosphorus flame retardant in a polyurethane foam material matrix, and simultaneously the prepared polyurethane foam material has uniform pore diameter and improves mechanical properties such as compression strength and the like after compounding the flame retardant and the polyurethane foam material.

The composite flame retardant prepared by intercalation compounding of the modified LDHs and the nitrogen-phosphorus flame retardant is added into a polyurethane foam material matrix, and plays roles in gas phase and condensed phase through heat absorption, surface coverage, char formation, combustion chain inhibition and the like, so that the polyurethane foam material is high-efficiency flame retardant, the polyurethane foam material is easier to generate a self-extinguishing phenomenon when a fire disaster occurs, and the diffusion and the spread of the fire disaster are effectively avoided.

The modified LDHs and the nitrogen-phosphorus flame retardant are not only dispersed in a foam system in a blending mode as a filler, but also participate in the reaction of a polyurethane matrix, and are cooperated with other components to form a copolymer, so that the flame retardance, the heat resistance, the moisture resistance and the corrosion resistance of the polyurethane foam material are improved.

In the application, the preferred phase change material is palmitic acid, contains carboxylic acid groups, not only can form strong hydrogen bonds with hydrophilic groups such as hydroxyl or amino in the composite flame retardant, but also can participate in the reaction process of isocyanate and polyol; finally, the reaction temperature of the reaction system is effectively reduced, and the problem of uneven dispersion of the composite flame retardant in the polyurethane foam material is solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

FIG. 1 is a graph of limiting oxygen index for flame retarded polyurethane foams of examples 1-5 and comparative examples 5 and 9.

FIG. 2 is a graph of vertical burning test for comparative examples 1 (a), 5 (b), 1 (c) and 6 (d).

FIG. 3 is a graph showing the change in light absorptivity versus time of the polyurethane foams of comparative examples 1 to 13, wherein (a) is the change in light absorptivity versus time of comparative examples 1 and 2 to 5, (b) is the change in light absorptivity versus time of comparative examples 1 and 6 to 9, and (c) is the change in light absorptivity versus time of comparative examples 1 and 10 to 13.

Fig. 4 shows the light absorptance versus time of comparative example 1 and examples 1 to 10, wherein (a) shows the light absorptance versus time of comparative example 1 (1#) and examples 1 to 5, and (b) shows the light absorptance versus time of comparative example 1 and examples 6 to 10.

FIG. 5 is a photomicrograph of cross-sectional cells of example 1 (d), example 6 (e), comparative example 1 (a), comparative example 9 (b) and comparative example 13 (c).

FIG. 6 is the center reaction temperature for the preparation of polyurethane foams of comparative examples 1, 9, 13 and examples 1, 6.

Fig. 7 is a bar graph of compressive strength for comparative example 1, comparative example 9, comparative example 13 and examples 1, 6.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The polyether polyol component and the isocyanate component used in the examples and comparative examples of the present application are commercially available products, which are purchased from Shanghai optical construction materials Co., ltd.

The preparation methods of the modified magnesium aluminum hydrotalcite in the examples and the comparative examples in the application are as follows:

adding water into the magnesium aluminum hydrotalcite to prepare hydrotalcite slurry;

weighing KH560 according to 3% of the mass of the magnesium aluminum hydrotalcite, adding the KH560 into absolute ethyl alcohol, and regulating the pH value to 5 by using glacial acetic acid to obtain KH560 solution;

and slowly dripping the KH560 solution into the hydrotalcite slurry, stirring for 4 hours, centrifuging, and drying to finish the surface modification to obtain the modified LDHs.

The preparation method of the composite flame retardant in the embodiment of the application comprises the following steps:

and mixing and grinding the modified LDHs and APP or MPP for 30min to obtain the composite flame retardant.

The preparation methods of the flame retardant polyurethane foam materials of the examples and comparative examples in the present application are as follows:

s1, stirring a polyether polyol component, palmitic acid and a composite flame retardant at room temperature until the components are uniformly stirred to obtain a uniformly mixed matrix material;

s2, mixing the isocyanate component with the matrix material, stirring for 10S, fully mixing, and performing chemical reaction to perform natural foaming;

and S3, standing for 5 minutes in a room temperature environment after the foam is stable, and obtaining the flame-retardant polyurethane foam material.

The raw material ratios of examples 1 to 10 and comparative examples 1 to 13 are shown in Table 1.

TABLE 1

1. Vertical burn (UL-94) test

The flame retardant properties were measured by a vertical burner (model JL-CZF-5, nanjing, lei Yiqi equipment Co., ltd.) and the vertical burning grade of the sample was measured according to the GB/T2408-1996 standard, the sample size was 10 mm. Times.10 mm. Times.150 mm, and the test results are shown in Table 2.

2. Limiting oxygen index determination

The limiting oxygen index LOI (%) was measured by a full-automatic limiting oxygen index measuring instrument (model JL-JF-5, nanjing Bright Lei Yiqi apparatus Co., ltd.) and the results are shown in Table 2.

TABLE 2 limiting oxygen index and UL-94 vertical burn test results for polyurethane foams

Note that: the first burning time of the sample is marked as T1, the second burning time is marked as T2, and the smoldering time is marked as T3.

As can be seen from the data of table 2, the limiting oxygen index of the pure polyurethane foam material prepared in comparative example 1 was only 18.9%, and it did not have flame retardant properties; after flame retardant modification of comparative examples 2 to 13 and examples 1 to 10, the limiting oxygen index is improved to different degrees, and the flame retardant property is enhanced.

Comparative examples 2 to 13 are polyurethane foams each having been modified LDHs, APP, MPP by the addition of different amounts (5 parts, 10 parts, 15 parts or 20 parts) alone. The data in Table 2 show that the flame retardant property of the polyurethane foam material can be enhanced by independently adding the modified LDHs, the limiting oxygen index of the polyurethane foam material monotonically increases along with the increase of the addition amount, but the increase range is smaller, and the limit oxygen index reaches 21.3 percent when 20 parts are added, and only increases by 2.4 percent; the flame retardant effect of the polyurethane foam added with MPP is slightly better than that of the polyurethane foam added with modified LDHs, the MPP is taken as a nitrogen-phosphorus flame retardant, the flame retardant property of the material can be improved through a nitrogen chemical mechanism and a condensation reaction, the limiting oxygen index of the polyurethane foam material is improved along with the increase of the addition amount, and the limiting oxygen index of the polyurethane foam material can reach 23.1% when 20 parts of the polyurethane foam material is added; the flame retardant effect of the polyurethane foam material with the APP added independently is best, the APP is an inorganic phosphorus flame retardant, the flame retardant property of the high polymer foam material can be improved through carbonization reaction and gas phase action, the limiting oxygen index of the high polymer foam material monotonically increases along with the increase of the addition amount, and when the addition amount is 20 parts, the limiting oxygen index of the foam material reaches the highest 23.6 percent.

Examples 1-10 are modified LDHs and APP or MPP compounded and added into polyurethane foam materials, and the flame retardant property of the foam materials is superior to that of the foam materials only added with one flame retardant. Examples 6 to 10 are modified LDHs and MPP which are used in a compounding way according to different proportions, and when the mass ratio is 4: at 16, limiting oxygen index is 23.3% at maximum, slightly increased compared to 23.1% of MPP alone; as shown by the experimental results of the limiting oxygen index in Table 2, the synergistic effect of the modified LDHs and APP is optimal, and the limiting oxygen index of the material can be obviously improved.

FIG. 1 is a graph of limiting oxygen index for flame retarded polyurethane foams of examples 1-5 and comparative examples 5 and 9. Examples 1 to 5 and comparative examples 5 and 9 are flame-retardant polyurethane foam materials prepared by compounding modified LDHs/APP with different mass ratios, the dotted line in FIG. 1 is a critical line, and data higher than the critical line shows that the compounding use of modified LDHs and APP has a synergistic effect on flame-retardant effect. From fig. 1, it can be seen that the oxygen index improvement of the polyurethane foam material by independently adding the modified LDHs is limited, but the flame retardant effect of the material can be obviously improved by adding the APP, the limiting oxygen index of the modified polyurethane foam material is gradually increased along with the increase of the proportion of the APP, and the synergistic effect is optimal when the proportion of the modified LDHs and the APP is 4:16, and the limiting oxygen index reaches 25.6%.

FIG. 2 is a graph of vertical burning test for comparative examples 1 (a), 5 (b), 1 (c) and 6 (d). As can be seen from the data of fig. 2 and table 1, the pure polyurethane foam material of comparative example 1 of fig. 2 (a) burns very rapidly, and burns completely for 17.8s, and flame can spread to the jig, with great safety hazards; as can be seen from fig. 2 (b), the polyurethane foam material with only modified LDHs added for about 20s forms a dense carbon layer, thereby achieving the flame retardant effect; FIG. 2 (c) shows that the flame-off 1s is extinguished immediately in the flame-retardant polyurethane foam material prepared in example 1, and the flame-retardant effect is obviously greatly improved; in example 6 of fig. 2 (d), the flame is automatically extinguished at about 4s, so that the burning time is effectively controlled, and the flame can be automatically extinguished quickly after the flame is far away from the fire source.

2. Smoke density test

The polyurethane foam material is cut into square blocks with the dimensions of 25mm multiplied by 6mm (thickness), the smoke density of a sample is measured by using a building material smoke density meter (model JL-JCY-3, nanjing, lei Yiqi equipment Co., ltd.) by taking GB/T8627-2007 (building material smoke density or decomposed smoke density experimental method) as a test standard, and the smoke density meter can measure the smoke generation amount of the material by the light intensity attenuation amount of transmitted smoke so as to evaluate the smoke generation conditions of different materials. The results were as follows:

FIG. 3 is a graph showing the change in light absorptivity versus time of the polyurethane foams of comparative examples 1 to 13, wherein (a) is the change in light absorptivity versus time of comparative examples 1 and 2 to 5, (b) is the change in light absorptivity versus time of comparative examples 1 and 6 to 9, and (c) is the change in light absorptivity versus time of comparative examples 1 and 10 to 13. It can be seen from FIG. 3 that the smoke increases sharply in a short period of time after the polyurethane foam of comparative example 1 is ignited, and then is maintained at a high level, and the absorption rate is reduced to various degrees by adding flame retardants of different systems (comparative examples 2 to 13). (a) The change relation curve of the light absorptivity and time of the polyurethane foam materials added with different amounts of modified LDHs independently shows that the smoke suppression effect is enhanced firstly and then reduced along with the increase of the addition amount, and the effect is optimal when the addition amount is 10 parts; (b) In order to independently add the APP, the light absorptivity changes with time, the smoke suppression effect is enhanced along with the increase of the addition amount, and when the addition amount is 20 parts, the smoke suppression effect is the best; (c) For the light absorptivity change curve with time when the MPP is added alone, the smoke density of the polyurethane foam material can be reduced when the MPP is added, but the influence of different addition amounts on the reduction of the smoke density amplitude is smaller.

Fig. 4 shows the light absorptance versus time of comparative example 1 and examples 1 to 10, wherein (a) shows the light absorptance versus time of comparative example 1 (1#) and examples 1 to 5, and (b) shows the light absorptance versus time of comparative example 1 and examples 6 to 10. It can be seen from fig. 3 (a) and (b) that the modified LDHs and APP or MPP still have good smoke suppression effect when added into the polyurethane foam material by compounding, but the smoke suppression effect of the polyurethane foam material is slightly affected by different compounding examples, wherein the compounding effect of example 1 is optimal.

In fig. 3 and 4, the meaning of # 1 is comparative example 1, the meaning of # 2 is comparative example 2, and the analogy to # 13 is comparative example 13; examples 1 to 10 correspond to examples 1 to 10, and the reference numerals correspond to examples.

Among them, the maximum smoke density values (SMD) and smoke density grades (SGD) of example 1 and comparative example 1 are shown in table 3.

TABLE 3 Table 3

As can be seen from the data in Table 3, the flame retardant polyurethane foam material prepared by the application can obviously reduce the smoke yield of the polyurethane foam material, and the maximum smoke density value (SMD) and the smoke density grade (SGD) are obviously reduced.

In conclusion, through a vertical combustion (UL-94) test, a limiting oxygen index measurement and a smoke density test, the flame-retardant polyurethane foam material prepared by the method has excellent flame retardance and smoke suppression performance, and can achieve the aim of high-efficiency flame retardance.

3. Flame retardant polyurethane foam cell structure analysis

FIG. 5 is a photomicrograph of cross-sectional cells of example 1 (d), example 6 (e), comparative example 1 (a), comparative example 9 (b) and comparative example 13 (c). As can be seen from FIG. 5, the cells in (b) to (e) all have polyhedral shapes, and the density of the cells is small, the matrix resin of the polyurethane foam material is small after the flame retardant is added, the liquid phase is stressed unevenly in the foaming process, and the pure polyurethane cells without the flame retardant in (a) have uniform and fine sizes. (b) And (c) flame retardant polyurethane foam materials of comparative examples 9 and 13 (20 parts of APP or MPP is added), wherein the APP and MPP are inorganic materials, so that the compatibility with a matrix is poor, the addition amount of the APP and MPP in the polyurethane foam material matrix is large, the dispersibility is poor, aggregation phenomenon occurs, the size distribution of the composite material is uneven, and the bubble and collapse phenomena are increased; (d) And (e) are the flame retardant polyurethane foam materials of the embodiment 1 and the embodiment 6, and after the APP and the MPP are compounded with the modified LDHs, the size of the polyurethane foam material pores is obviously changed compared with that of the polyurethane foam material pores which are independently added, and the foam material pores tend to be uniform.

4. Maximum reaction temperature variation of flame retardant polyurethane foam material

The center reaction temperatures of comparative examples 1, 9, 13 and 1, 6 for the polyurethane foam preparation were measured by a thermocouple thermometer, and the results are shown in fig. 6.

Fig. 6 shows the center reaction temperatures of comparative examples 1, 9, 13 and 1, 6 for the preparation of polyurethane foam, and it can be seen from fig. 6 that the center reaction temperatures of the polyurethane foam prepared in example 1 and 6 according to the present application are all 100 c or less.

5. Compression strength variation of flame retardant polyurethane foam

Fig. 7 is a bar graph of compressive strength for comparative example 1, comparative example 9, comparative example 13 and examples 1, 6.

Since the flame retardants of comparative examples 9, 13 and 1, 6 are inorganic materials and are added to the polyurethane matrix in a physical addition manner, the uniformity of dispersion affects the growth of cells during the polyurethane reaction and damages the cell structure thereof. From the analysis of the cell structure in fig. 5, it is clear that the addition of APP and MPP causes a different degree of damage to the cell structure of the flame retardant polyurethane foam, which is one of the reasons for its reduced compressive strength, consistent with the bar graph results of fig. 7. After the APP and the MPP are subjected to intercalation compounding with the surface modified LDHs, the problems of poor compatibility and poor dispersibility are solved to a certain extent, and the compression strength is improved to some extent, which is consistent with the analysis result of the cell structure in FIG. 5.

In conclusion, the composite flame retardant prepared by intercalation compounding of the modified LDHs and the nitrogen-phosphorus flame retardant is added into a polyurethane foam material matrix, and the high-efficiency flame retardance of the polyurethane foam material is realized by the actions of heat absorption, surface coverage, char formation, combustion chain inhibition and the like in a gas phase and a condensed phase, so that the self-extinguishing phenomenon of fire release is easier to occur when the polyurethane foam material is in a fire disaster, and the diffusion and the spread of the fire disaster are effectively avoided.

In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (9)

1. The flame-retardant polyurethane foam material is characterized by comprising the following raw materials in parts by mass:

57 parts of polyether polyol component, 43 parts of isocyanate component, 3-8 parts of phase change material and 20 parts of composite flame retardant;

the composite flame retardant is prepared by intercalation compounding of modified magnesium aluminum hydrotalcite and a nitrogen-phosphorus flame retardant;

the modified magnesium aluminum hydrotalcite is obtained by carrying out surface modification on magnesium aluminum hydrotalcite by a silane coupling agent.

2. The flame retardant polyurethane foam material of claim 1, wherein the phase change material comprises one of lauric acid, capric acid, palmitic acid, caprylic acid, n-octadecane, and n-eicosane.

3. The flame retardant polyurethane foam material according to claim 1, wherein the mass ratio of the modified magnesium aluminum hydrotalcite to the nitrogen-phosphorus flame retardant is 1-19:1-19.

4. The flame retardant polyurethane foam of claim 1, wherein the method of surface modification comprises:

adding water into the magnesium aluminum hydrotalcite to prepare hydrotalcite slurry;

weighing a silane coupling agent according to the mass of 3-7% of the magnesium aluminum hydrotalcite, adding the silane coupling agent into absolute ethyl alcohol, and regulating the pH value to be 5 by using glacial acetic acid to obtain a silane coupling agent solution;

slowly dripping the silane coupling agent solution into the hydrotalcite slurry, stirring for 4 hours, centrifuging, and drying to finish the surface modification treatment.

5. The flame retardant polyurethane foam according to claim 1, wherein the nitrogen-phosphorus flame retardant is ammonium polyphosphate or melamine phosphate.

6. A method for producing the flame retardant polyurethane foam according to any one of claims 1 to 5, comprising:

preparing a polyether polyol component, an isocyanate component, a phase change material and a composite flame retardant according to parts by mass;

and uniformly mixing the polyether polyol component, the phase change material and the composite flame retardant, adding the isocyanate component, uniformly stirring, and naturally foaming and curing to obtain the flame-retardant polyurethane foam material.

7. Use of a flame retardant polyurethane foam according to any of claims 1 to 5 in mines.

8. A method for reducing the highest reaction temperature of a flame-retardant polyurethane foam material is characterized in that a phase change material is added into raw materials of the flame-retardant polyurethane foam material, and the addition amount of the phase change material is 3-8% of the total mass of a polyether polyol component and an isocyanate component.

9. The method of lowering the maximum reaction temperature of a flame retardant polyurethane foam according to claim 8, further comprising adding a composite flame retardant in an amount of 5 to 20% by weight based on the total mass of the polyether polyol component and the isocyanate component;

the composite flame retardant is prepared by intercalation compounding of modified magnesium aluminum hydrotalcite and a nitrogen-phosphorus flame retardant;

the modified magnesium aluminum hydrotalcite is obtained by carrying out surface modification on magnesium aluminum hydrotalcite by a silane coupling agent.