Application of nano purple phosphorus as high polymer material flame retardant

Abstract

The invention belongs to the technical field of flame-retardant materials, and particularly relates to application of nano purple phosphorus as a high polymer material flame retardant. The invention provides an application of nano purple phosphorus as a high polymer material flame retardant and a high polymer flame-retardant material, the nano purple phosphorus has the characteristics of small nano size, high thermal stability and environmental stability, excellent mechanical properties and the like, and can effectively improve the flame-retardant effect of the high polymer material when being used as a high polymer material flame-retardant additive; the flame retardant using nano purple phosphorus as a polymer matrix material not only can overcome the problems of large particles, non-uniform dispersion, low phosphorus content, easy volatilization, easy moisture absorption and degradation, poor compatibility and the like of the existing phosphorus-based flame retardant, but also has the advantages of low toxicity, low smoke, no halogen and the like; and the flame retardant conforms to the current environment-friendly development trend of flame retardants.

Description

Technical Field

[0001] The invention belongs to the technical field of flame retardant materials, and more specifically relates to the application of nano purple phosphorus as a flame retardant for polymer materials. Background Art

[0002] As the use of high molecular polymers becomes more and more widespread, they generally have the disadvantage of being flammable, which seriously threatens the safety of life and property. The development and utilization of flame retardants are of great significance to protecting life, health and property safety. Common flame retardants include halogen flame retardants and phosphorus flame retardants. The large-scale use of halogen flame retardants will cause great harm to human living environment and physical health, and some products have been expressly banned. As environmental protection and health concepts receive more and more attention, phosphorus-based flame retardants are recognized as the most superior halogen-free flame retardant alternatives. Phosphorus-based flame retardants can achieve flame retardancy without halogen and are safer. Phosphorus-based flame retardants have quickly gained public recognition due to their high flame retardant efficiency, low corrosion during processing, excellent plastic molding flowability, low toxicity and low corrosive gas emissions.

[0003] However, organic phosphorus flame retardants in phosphorus flame retardants have disadvantages such as high volatility, large smoke generation during combustion, and poor thermal stability. In addition, their phosphorus content is relatively low, and they can only achieve a good flame retardant effect when added in large quantities. Traditional inorganic phosphorus flame retardants (such as red phosphorus and polyphosphoric acid amines, etc.) have problems with poor polymer compatibility and uneven dispersion due to their large particle size, which hinders their flame retardant properties. Nano black phosphorus, as a new type of fine phosphorus chemical product, has the advantages of low dosage and good flame retardant effect when used for flame retardant polymer materials. However, nano black phosphorus has poor environmental stability and is easily oxidized and degraded, resulting in decreased performance, which affects the long-term flame retardant effect. With the increasing requirements for material performance, the development of new flame retardant materials has become a top priority. Summary of the invention

[0004] The purpose of the present invention is to provide an application of nano purple phosphorus as a flame retardant for polymer materials, and to solve the problems existing in the above-mentioned prior art by adding nano purple phosphorus to polymer materials, so as to achieve a significant improvement in the flame retardant performance of the material.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention is to provide an application of nano purple phosphorus as a flame retardant for polymer materials.

[0007] Furthermore, at least one dimension of the three-dimensional dimensions of the nano purple phosphorus is 0.5-100 nm.

[0008] The nano purple phosphorus includes at least one of purple phosphorene, purple phosphorus quantum dots, purple phosphorus nanobelts, purple phosphorus nanowires and purple phosphorus nanotubes, or powder of purple phosphorus crystals whose size reaches the above range after grinding.

[0009] Furthermore, the amount of the nano purple phosphorus added as a flame retardant of the polymer material is 0.1%-15% of the mass of the polymer material.

[0010] In some optional schemes, the nano purple phosphorus is added in the form of solid, water dispersion or organic solution dispersion, wherein the solid content of the water dispersion or organic solution dispersion is 0.01-10 mg / L.

[0011] The present invention can adopt different adding methods according to the different initial forms of the base material. For thermoplastic polymer materials that adopt the melt blending method to add flame retardants, nano purple phosphorus dispersion or nano purple phosphorus powder is added; for polymer materials that need to add flame retardants at a lower temperature, organic solvent dispersion is mixed with organic liquid phase base materials; for thermosetting polymer materials, nano purple phosphorus solid powder is directly mixed and used.

[0012] In some optional embodiments, the diameter of the purple phosphorus quantum dots is 0.5-20 nm.

[0013] In some optional embodiments, the purple phosphorene has a sheet thickness of 0.5-30 nm and a plane diameter of 20-200 nm.

[0014] Nano purple phosphorus generally presents a layered structure, with a pyrolysis temperature of up to 512°C and extremely high thermal stability. The two-dimensional Young's modulus of a single layer of purple phosphorus is approximately 1512±76N / m, which is 4.4 times that of graphene and much higher than other two-dimensional materials, and has excellent mechanical properties. Nano purple phosphorus was ultrasonically dispersed in deionized water and placed in an air environment for ten days without being oxidized and degraded, indicating that nano purple phosphorus has excellent environmental stability. Nano purple phosphorus has superior properties than other flame retardants in terms of mechanical properties, thermal stability and environmental stability, which enables nano purple phosphorus to exert a super high flame retardant effect while ensuring the mechanical properties and environmental stability of the material.

[0015] The second technical solution of the present invention is to provide a polymer flame retardant material, which comprises a polymer matrix material and 0.1%-15% of the mass of the polymer matrix material of nano purple phosphorus;

[0016] The polymer matrix material includes polyurethane polymer material, polypropylene resin or polyvinyl chloride.

[0017] The nano purple phosphorus used in the present invention has a relatively small size and can be directly and evenly dispersed in a polymer matrix material without coating or modification, and has good dispersibility and compatibility.

[0018] The third technical solution of the present invention is to provide a method for preparing the above-mentioned polymer flame retardant material, the steps comprising: evenly mixing the nano purple phosphorus and the polymer matrix material, and then subjecting the mixture to a molding process to obtain the polymer flame retardant material.

[0019] Furthermore, the molding process includes dry molding or melt extrusion molding.

[0020] The nano purple phosphorus in the present invention is prepared into polymer flame retardant materials by using different equipment according to different polymer matrix materials, wherein nano purple phosphorus with different morphologies, different sizes, different thicknesses and different specifications is used as a flame retardant component according to the requirements of different polymer flame retardant materials. In the selection of the morphology of the nano purple phosphorus flame retardant, nano purple phosphorus with different morphologies is selected according to the performance requirements of the polymer material. For example, for materials that require excellent flame retardant properties, nano purple phosphorus with a sheet structure can be selected, because nanoparticles with a sheet structure have an excellent flame retardant effect; for materials that need to improve the strength and toughness of the material, nano purple phosphorus with a linear or ribbon shape can be selected; in the selection of size, the size of the nano purple phosphorus should match the length of the molecular chain segment of the polymer material. For polymer materials with longer molecular segments, such as polyethylene and polypropylene, larger nano purple phosphorus can be selected to better entangle with the polymer segments and improve the flame retardant effect; for polymer materials with shorter molecular segments, such as epoxy resin, smaller nano purple phosphorus can be selected; in terms of thickness selection, for materials that need to form a flame retardant coating, such as polyimide, thinner nano purple phosphorus can be selected to form a dense flame retardant layer in the coating; for materials that need to improve the internal flame retardant properties of the material, nano purple phosphorus with moderate thickness can be selected; in terms of the selection of nano purple phosphorus specifications, different specifications of nano purple phosphorus can be selected according to the processing technology and equipment requirements of the polymer material. For example, in the process of melt blending, nano purple phosphorus powder with smaller particle size and better fluidity can be selected to better mix with the polymer melt; in the coating process, nano purple phosphorus dispersion with good dispersibility can be selected.

[0021] The fourth technical solution of the present invention is to provide an application of the above-mentioned polymer flame retardant material as a building material in the construction field.

[0022] The present invention discloses the following technical effects:

[0023] The invention provides a new use of nano violet phosphorus for flame retardant polymer materials. The nano violet phosphorus has the characteristics of small nano size, high thermal stability and environmental stability, excellent mechanical properties, etc. When used as a flame retardant additive for polymer materials, it can effectively improve the flame retardant effect of polymer materials, which is of great significance for promoting the green development of the flame retardant industry.

[0024] The flame retardant using nano purple phosphorus as a polymer matrix material can not only overcome the problems of existing phosphorus-based flame retardants such as large particles, uneven dispersion, low phosphorus content, easy volatility, easy moisture absorption and degradation, and poor compatibility, but also has the advantages of low toxicity, low smoke and halogen-free, and is in line with the current development trend of green and environmentally friendly flame retardants.

[0025] The addition of nano purple phosphorus to the polymer flame retardant material prepared by the invention not only improves the flame retardant effect of the material, but also maintains the mechanical strength and environmental stability of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 This is a physical picture of the purple phosphorene aqueous dispersion in Example 1.

[0028] Figure 2 These are characterization diagrams of phosphene in the phosphene aqueous dispersion in Example 1, wherein (a)-(c) are TRM diagrams, (d) is an EDS diagram, and (e)-(g) are element distribution diagrams.

[0029] Figure 3 This is the HR-TEM image of phosphene in the phosphene aqueous dispersion in Example 1.

[0030] Figure 4 These are physical pictures of the materials prepared in Example 1 and Comparative Example 1, wherein (a) is Comparative Example 1 and (b) is Example 1.

[0031] Figure 5 The ignition test results of the long strip samples prepared in Example 1 and Comparative Example 1 are shown, wherein (a) is Comparative Example 1 and (b) is Example 1. DETAILED DESCRIPTION

[0032] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0033] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0034] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0035] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0036] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0037] The nano purple phosphorus used in the specific embodiment of the present invention can be selected from commercially available products, or prepared by a top-down method or a bottom-up method, wherein the top-down method includes ultrasonic stripping, shear stripping or electrochemical stripping, and the bottom-up method includes an ammonium salt catalysis method.

[0038] The specific steps of preparing purple phosphorus quantum dots, purple phosphorene, purple phosphorus nanowires, purple phosphorus nanobelts, and purple phosphorus nanotubes by the top-down method or the bottom-up method are not limited, and they can be prepared by conventional methods, wherein at least one of the three-dimensional dimensions of the nano purple phosphorus used in the embodiment of the present invention is between 0.5-200nm.

[0039] Example 1

[0040] The preparation steps of polymer flame retardant materials include:

[0041] S1. Using an aqueous polyurethane emulsion (polyurethane solid content of 40%) as a matrix material, and then adding 0.4% of purple phosphorene by mass of the matrix material to obtain a polymer flame retardant material precursor; wherein purple phosphorene is added in the form of an aqueous dispersion, and the preparation steps are: under the protection of an inert atmosphere, a block of single-crystal purple phosphorus is placed in an agate mortar and ground for 2 hours to obtain purple phosphorus powder, ultrapure water is used as a dispersant, and the mixture is stirred and mixed to obtain a mixed solution with a solid-liquid ratio of mg:mL of 1, and ultrasonically treated (200W) for 24 hours, and then centrifuged at a rate of 3000rpm, and the supernatant is taken to obtain a purple phosphorene aqueous dispersion with a solid content of 0.2mg / mL;

[0042] S2. Place the polymer flame retardant material precursor in an ultrasonic cleaner and shake for 30 minutes to mix evenly, then vacuum dry for 48 hours (40° C.) to completely evaporate the water to obtain a purple phosphorene-polyurethane solid film.

[0043] Figure 1 This is a physical picture of the purple phosphorene aqueous dispersion in Example 1.

[0044] Figure 2 These are characterization diagrams of phosphene in the phosphene aqueous dispersion in Example 1, wherein (a)-(c) are TRM diagrams, (d) is an EDS diagram, and (e)-(g) are element distribution diagrams.

[0045] Figure 3 This is the HR-TEM image of phosphene in the phosphene aqueous dispersion in Example 1.

[0046] Depend on Figure 2-Figure 3 From the transmission electron microscope observation results, it can be seen that the maximum average diameter of the obtained nano purple phosphorus is 14.75nm. The prepared nano purple phosphorus has a small particle size, which is beneficial to improving the dispersibility in polymer materials.

[0047] Comparative Example 1

[0048] The preparation steps of polymer materials include:

[0049] S1, using an aqueous polyurethane emulsion (polyurethane solid content of 40%) as a matrix material, and then adding high-purity water of an equal volume to the purple phosphorene aqueous dispersion of Example 1 to obtain a polymer material precursor;

[0050] S2. Place the polymer material precursor in an ultrasonic cleaner and shake for 30 minutes to mix evenly, then vacuum dry for 48 hours (40° C.) to completely evaporate the water to obtain a polyurethane solid film.

[0051] Figure 4 These are physical pictures of the materials prepared in Example 1 and Comparative Example 1, wherein (a) is Comparative Example 1 and (b) is Example 1.

[0052] The long strip samples were prepared by the methods of Example 1 and Comparative Example 1 and the ignition test was carried out. The results are as follows: Figure 5 shown.

[0053] Figure 5 The ignition test results of the long strip samples prepared in Example 1 and Comparative Example 1 are shown in Figure 1, where (a) is Comparative Example 1 and (b) is Example 1. As can be seen from the figure, the oxygen index of the waterborne polyurethane film with purple phosphorene added is significantly improved, and it is difficult to ignite, easy to self-extinguish, has less droplets, less smoke, and a slow burning speed. After burning, the surface is flat and no wire drawing occurs, which shows that the waterborne polyurethane film with purple phosphorene added has excellent flame retardant properties.

[0054] Example 2

[0055] The preparation steps of polymer flame retardant materials include:

[0056] S1, using water-based polyurethane emulsion (polyurethane solid content of 40%) as matrix material, and then adding 0.4% of the matrix material mass of nano purple phosphorus (powdered) to obtain a polymer flame retardant material precursor; wherein, the nano purple phosphorus is mixed by placing white phosphorus and ammonium salt (ammonium chloride) in a quartz tube under vacuum conditions at a mass ratio of 1:5, vacuum sealing is performed at a distance of 15 cm from the bottom of the quartz tube to ensure the airtightness of the reaction, and then the vacuum-sealed quartz tube is placed in a muffle furnace, and naturally cooled to room temperature after high temperature (550°C) heat treatment for 12h, washed with ethanol and separated by 3 centrifugations (10000rpm, 5min), and after drying, placed in an agate mortar and ground for 1h to obtain a nano purple phosphorus powder with a particle size between 20-100μm;

[0057] S2. Place the polymer flame retardant material precursor in a stirring container with a magnetic stirrer and stir for 3 hours to disperse it evenly, and vacuum dry it (40° C.) to remove the solvent to obtain a nano purple phosphorus-polyurethane solid film.

[0058] After testing, the nano purple phosphorus-polyurethane solid film obtained in this embodiment has a significantly improved oxygen index compared with the pure polyurethane film, and is difficult to ignite, easy to self-extinguish, produces less smoke, has a slow burning speed, has fewer droplets, and has a smooth surface after burning without any wire drawing phenomenon. This shows that the material prepared by adding nano purple phosphorus in solid form also has excellent flame retardant properties.

[0059] Example 3

[0060] The preparation steps of polymer flame retardant materials include:

[0061] S1. Using an aqueous polyurethane emulsion (polyurethane solid content of 40%) as a matrix material, and then adding 0.1% of purple phosphorene by mass of the matrix material to obtain a polymer flame retardant material precursor; wherein purple phosphorene is added in the form of an aqueous dispersion, and the preparation steps are: under the protection of an inert atmosphere, a block of single-crystal purple phosphorus is placed in an agate mortar and ground for 4 hours to obtain purple phosphorus powder, ultrapure water is used as a dispersant, and the mixture is stirred and mixed uniformly to obtain a mixed solution with a solid-liquid ratio of mg:mL of 6, ultrasonically treated (500W) for 8 hours, and then centrifuged at a rate of 4000rpm, and the supernatant is taken to obtain a purple phosphorene aqueous dispersion with a solid content of 0.50mg / mL, a purple phosphorene maximum surface average diameter of 100nm, and an average thickness of 20nm;

[0062] S2. Place the polymer flame retardant material precursor in an ultrasonic cleaner and shake for 2 hours to mix evenly, then vacuum dry for 72 hours (40° C.) to completely evaporate the water to obtain a purple phosphorene-polyurethane solid film.

[0063] An ignition experiment was conducted on the purple phosphorene-polyurethane solid film prepared in this embodiment. The results showed that the purple phosphorene-polyurethane solid film prepared in this embodiment was difficult to ignite, easy to self-extinguish, produced less smoke, had a slow burning speed, and had less droplets. After burning, the surface was smooth and no wire drawing occurred, further indicating that the water-based polyurethane with added nano purple phosphorus had excellent flame retardant properties.

[0064] Example 4

[0065] The preparation steps of polymer flame retardant materials include:

[0066] S1, drying polypropylene resin, controlling the moisture content below 0.1%, as a matrix material, and then adding 5% of the matrix material mass of nano purple phosphorus (powder) to obtain a polymer flame retardant material precursor; wherein the nano purple phosphorus is added in the form of a dispersion, and the preparation steps are: under the protection of an inert atmosphere, a block of single crystal purple phosphorus is placed in an agate mortar and ground for 1h to obtain purple phosphorus powder, anhydrous ethanol is used as a dispersant, and the mixture is stirred and mixed to obtain a mixed solution, the solid-liquid ratio mg:mL is 5, and ultrasonic (200W, 40°C) treatment is performed for 8h (ultrasonic vibration under an ice bath), and then centrifuged at a rate of 200rpm, and the obtained supernatant is filtered through a microporous membrane of 0.02μm, and then the solid attached to the microporous membrane is placed in anhydrous ethanol again, and ultrasonic vibration is continued for 2h to obtain a nano purple phosphorus dispersion, the solid content is 1mg / mL, the size is that the maximum surface average diameter is 200nm, and the average thickness is 20nm;

[0067] S2. The polymer flame retardant material precursor is stirred and dried in a container, then fed into a twin-screw extruder from a metering feeder for plasticization and melting, and then extruded (200°C, inert gas protection), cooled, and dried at room temperature for 3 days under vacuum conditions to obtain a polymer flame retardant material (nano purple phosphorus-polypropylene material).

[0068] An ignition experiment was carried out on the nano purple phosphorus-polypropylene material prepared in this embodiment. The results showed that the nano purple phosphorus-polypropylene material prepared in this embodiment was difficult to ignite, easy to self-extinguish, produced less smoke, had a slow burning speed, and had less droplets. After burning, the surface was flat and no wire drawing occurred, further illustrating that the polypropylene plastic added with nano purple phosphorus has excellent flame retardant properties.

[0069] Example 5

[0070] The preparation steps of polymer flame retardant materials include:

[0071] S1, using polyvinyl chloride as a matrix material, and then adding 3% of the matrix material mass of nano purple phosphorus (powder) to obtain a polymer flame retardant material precursor; wherein the nano purple phosphorus is added in the form of a dispersion, and the preparation steps are: under the protection of an inert atmosphere, a block of single crystal purple phosphorus is placed in an agate mortar and ground for 4 hours to obtain purple phosphorus powder, anhydrous ethanol is used as a dispersant, and the mixture is stirred and mixed to obtain a mixed solution, the solid-liquid ratio mg:mL is 5, and ultrasonic (800W, 40°C) treatment is performed for 3 hours (ultrasonic vibration in an ice bath), and then centrifuged at a speed of 3500rpm, and the obtained supernatant is the nano purple phosphorus dispersion, the solid content is 0.2mg / mL, the maximum average diameter of the nano purple phosphorus is 100nm, and the average thickness is 25nm;

[0072] S2. The polymer flame retardant material precursor is stirred and dried in a container, then fed into a twin-screw extruder from a metering feeder for plasticization and melting, and then extruded (200° C., inert gas protection), cooled, and dried at room temperature for 3 days under vacuum conditions to obtain a polymer flame retardant material (nano purple phosphorus-polyvinyl chloride material).

[0073] An ignition experiment was carried out on the nano purple phosphorus-polyvinyl chloride material prepared in this embodiment. The results showed that the nano purple phosphorus-polyvinyl chloride material prepared in this embodiment was difficult to ignite, easy to self-extinguish, produced less smoke, had a slow burning speed, and had less droplets. After burning, the surface was smooth and no wire drawing phenomenon occurred, further indicating that the polyvinyl chloride plastic added with nano purple phosphorus has excellent flame retardant properties.

[0074] Example 6

[0075] The preparation steps of polymer flame retardant materials include:

[0076] S1. A polyurethane rigid foam material is used as a matrix material, and 0.5% of the mass of the matrix material is added with nano purple phosphorus (purple phosphorus quantum dots) to obtain a polymer flame retardant material precursor; wherein the nano purple phosphorus is added in the form of a dispersion, and the preparation steps are as follows: under the protection of an inert atmosphere, a block of single crystal purple phosphorus is placed in an agate mortar and ground for 1 hour to obtain purple phosphorus powder, N-methylpyrrolidone (NMP) is used as a dispersant, and the mixture is stirred and mixed to obtain a mixed solution with a solid-liquid ratio of mg:mL of 10, and an inert gas is used to empty the shearing machine. The air in the mixture was poured into a high-speed shearing machine, the speed of the shearing machine was set to 5000rpm, the shearing time was 3h, and a suspension with good peeling effect was obtained. The obtained suspension was centrifuged at a speed of 8000rpm, and the supernatant was filtered with a 0.02pm microporous membrane. The filtrate was placed in a vacuum drying oven at room temperature to obtain a concentrated purple phosphorus quantum dot NMP dispersion. The obtained purple phosphorus quantum dot had an average particle size of 10nm and a dispersion solid content of 1.0mg / mL.

[0077] S2. Stir and mix the polymer flame retardant material precursor in a container, pour it into a mold, and solidify it to obtain the polymer flame retardant material (purple phosphorus quantum dots-polyurethane rigid foam material).

[0078] An ignition experiment was carried out on the purple phosphorus quantum dot-polyurethane rigid foam material prepared in this embodiment. The results showed that the purple phosphorus quantum dot-polyurethane rigid foam material prepared in this embodiment was difficult to ignite, easy to self-extinguish, produced less smoke, had a slow burning speed, and had fewer molten droplets. After burning, the surface was flat and no wire drawing phenomenon occurred, further illustrating that the polyurethane rigid foam material with added nano purple phosphorus has excellent flame retardant properties.

[0079] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0080] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. Application of nano purple phosphorus as a flame retardant for polymer materials.

2. The use according to claim 1, characterized in that At least one dimension of the three-dimensional dimensions of the nano purple phosphorus is 0.5-100 nm.

3. The use according to claim 1, characterized in that The addition amount of the nano purple phosphorus as a flame retardant of the polymer material is 0.1%-15% of the mass of the polymer material.

4. A polymer flame retardant material, characterized in that: The polymer flame retardant material comprises a polymer matrix material and 0.1%-15% of the mass of the polymer matrix material is nano purple phosphorus.

5. The polymer flame retardant material according to claim 4, characterized in that: The nano purple phosphorus comprises at least one of purple phosphorene, purple phosphorus quantum dots, purple phosphorus nanobelts, purple phosphorus nanowires and purple phosphorus nanotubes; and / or at least one of the three-dimensional dimensions of the nano purple phosphorus is 0.5-100 nm.

6. The polymer flame retardant material according to claim 4, characterized in that: The polymer matrix material includes polyurethane polymer material, polypropylene resin or polyvinyl chloride.

7. The method for preparing a polymer flame retardant material according to any one of claims 4 to 6, characterized in that: The steps include: The nano purple phosphorus and the polymer matrix material are uniformly mixed and then subjected to a molding process to obtain the polymer flame retardant material.

8. The preparation method according to claim 7, characterized in that: The molding process includes dry molding or melt extrusion molding.

9. Use of the polymer flame retardant material according to any one of claims 4 to 6 as a building material in the field of construction.

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