A nitrogen-bromine organic framework material, a fireproof coating and preparation methods thereof

Abstract

The application discloses a nitrogen-bromine organic framework material, a fireproof coating and a preparation method thereof, and belongs to the technical field of protective fire-retardant coatings. The fireproof coating comprises, in parts by mass, 100-120 parts of water-based epoxy resin, 15-30 parts of nitrogen-bromine organic framework material, 10-20 parts of flame-retardant additive, 40-55 parts of curing agent, 10-15 parts of additive and 10-15 parts of water. The nitrogen-bromine organic framework material is a cyclic structure prepared from 2,5-dibromo-p-phenylenediamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, and the nitrogen-bromine organic framework material is beneficial to the adsorption of combustible materials; the fireproof coating obtained by adding the nitrogen-bromine organic framework material has excellent flame-retardant performance and mechanical properties.

Description

Technical Field

[0001] This invention belongs to the field of protective flame-retardant coating technology, and more specifically, relates to a nitrogen-bromine organic framework material, a fire-retardant coating, and a method for preparing the same. Background Technology

[0002] Steel structures are excellent conductors of heat, and their load-bearing capacity and structural strength decrease during fires, potentially leading to building collapse and severe casualties and property damage. Applying specialized fire-retardant coatings to steel structures is one of the most convenient and effective measures for fire protection. Epoxy intumescent fire-retardant coatings are made by grinding and dispersing epoxy resin as a base material, with added fire-retardant fillers, pigments, and additives. However, current fire-retardant fillers have low flame-retardant efficiency, and excessive addition increases the deflection properties and brittleness of epoxy resin, significantly limiting their practical application. Adding nanofillers to epoxy-based coatings is an advanced strategy for achieving high-performance nanocomposite materials with excellent thermal and mechanical properties. Metal-organic frameworks (MOFs), as advanced functional materials with nanopore morphology and porosity, possess advantages such as controllable pore size, low density, and large specific surface area, and have been widely used in photocatalysis, catalysis, and adsorption. Based on these unique characteristics, MOFs are used to develop advanced composite materials with excellent thermal and mechanical properties.

[0003] A search revealed that the patent publication number is CN1478123A, published on February 25, 2004, which discloses a flame-retardant polyurethane composition containing ethylene bis(tetrabromophthalimide) and / or tris(2,3-dibromopropyl)isocyanurate as flame retardant components, and also includes antimony trioxide, which does not have an intumescent flame-retardant effect.

[0004] In addition, patent publication number CN102746774A, publication date October 24, 2012, patent titled "Brominated Alkyd Resin Finishing Fire-retardant Coating and its Preparation Method," describes the composition of the bromine alkyd resin finishing fire-retardant coating as follows: bromine alkyd resin, ammonium polyphosphate, melamine, pentaerythritol, antimony trioxide, zinc borate, titanium dioxide, molybdenum trioxide, dimethyl silicone oil, drying agent, and solvent; its preparation steps are as follows: [The text abruptly ends here, likely due to an incomplete sentence or missing information.] Pentaerythritol, antimony trioxide, zinc borate, titanium dioxide, and molybdenum trioxide are sequentially added to a multi-purpose dispersing mill and dispersed at high speed for 30-60 minutes. The stirring speed is then reduced, brominated alkyd resin is added, and dispersion continues for 20-40 minutes. Dimethyl silicone oil is added, and the mixture is ground to the desired fineness using a conical mill. Finally, it is dispersed in a multi-purpose dispersing mill for 10-20 minutes, and a drying agent is added and dispersed evenly to obtain the product. This product utilizes conventional flame retardants in combination, but the flame retardant efficiency is relatively low. In the above scheme, the fire-retardant coating has low stability, and the components are free in the coating, making it prone to brittleness and limiting its fire-retardant performance. Summary of the Invention

[0005] 1. The problem to be solved

[0006] To address the problems of brittleness and flammability in existing fire-retardant coatings, this invention provides a nitrogen-bromine organic framework material and its preparation method, which facilitates the adsorption of combustibles.

[0007] The present invention also provides a fire-retardant coating and its preparation method. By adding the above-mentioned nitrogen-bromine organic framework material, the obtained fire-retardant coating has excellent flame retardant properties and mechanical properties.

[0008] 2. Technical Solution

[0009] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0010] A nitrogen-bromine organic framework material, wherein the nitrogen-bromine organic framework material is a cyclic structure prepared from 2,5-dibromo-p-phenylenediamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, which is obtained by reacting the -NH2 in 2,5-dibromo-p-phenylenediamine with the -C=O in 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine.

[0011] The nitrogen-bromine organic framework material prepared by this invention has a single pore size of about 100 nm, and the particle size formed by multiple pores is 1 to 4 μm. If the particle size is too large, it will affect the strength of the fire retardant coating and cannot effectively improve the mechanical properties of the composite material. If it is too small, it will easily agglomerate and affect its dispersibility.

[0012] This invention also discloses a method for preparing the above-mentioned nitrogen-bromine organic framework material, specifically including the following steps:

[0013] Step a, Dissolution: Add 2,5-dibromo-p-phenylenediamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to a solvent and mix thoroughly to obtain a mixed solution. Preferably, the mixture is dispersed by ultrasonic vibration for 30 min. The solvent is one or more of toluene, benzene, and acetone, preferably toluene, but it can also be benzene and acetone, as long as it can completely dissolve the reactants. The preferred amount of solvent added is 20 mL.

[0014] Step b, adding acid: Add an acid solution to the mixed solution obtained in step a, mix evenly, preferably by ultrasonic vibration for 30 min; wherein, the acid is preferably nitric acid, used to provide acidic conditions and promote the reaction process. In addition to nitric acid, sulfuric acid and acetic acid can also be used, and the amount of acid added is preferably 10 mL;

[0015] Step c, reaction: Transfer the mixture obtained in step b to a reaction vessel and react at a certain temperature;

[0016] Step d: Cooling, centrifugation, washing three times, and drying to obtain nitrogen-bromine organic framework material.

[0017] The mass ratio of 2,5-dibromo-p-phenylenediamine to 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine is (1.0-1.5):(1.5-1.9).

[0018] Furthermore, the molar ratio of the acid to 2,5-dibromo-p-phenylenediamine in step b is 1:(1.8-2.9).

[0019] Furthermore, the acid mentioned in step b is one or more of nitric acid, sulfuric acid, and acetic acid, with a preferred concentration of 0.2 mol / L.

[0020] Furthermore, in step c, the reaction temperature is 150–160°C, and the reaction time is 24–36 h.

[0021] Furthermore, in step d, the drying temperature is 50℃ and the drying time is 24h.

[0022] This invention discloses a fire-retardant coating based on the above-mentioned nitrogen-bromine organic framework material, comprising 100-120 parts of waterborne epoxy resin, 15-30 parts of nitrogen-bromine organic framework material, 10-20 parts of flame retardant additive, 40-55 parts of curing agent, 10-15 parts of additive, and 10-15 parts of water.

[0023] The flame retardant additive is a mixture of antimony trioxide, ammonium polyphosphate, pentaerythritol and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, in a mass ratio of 1:2:10:2.

[0024] The curing agent is diethylenetriamine. In addition to diethylenetriamine, it can also be ethylenediamine and polyamide, which are used to cure waterborne epoxy resins.

[0025] The additives include an organosilicon defoamer and glass fiber, wherein the ratio of the organosilicon defoamer to glass fiber is 1:5. The organosilicon defoamer is one or more of dimethyl silicone oil, fluoroalkyl silicone oil, and long-chain alkyl silicone oil, used to eliminate bubbles. The glass fiber has a length of one or more of 0.5-1cm, 1-2cm, and 2-4cm, used to improve strength.

[0026] This invention also discloses a preparation process for the above-mentioned fire-retardant coating, comprising the following steps:

[0027] Step a: Mix waterborne epoxy resin, nitrogen-bromine organic framework material, flame retardant additives, auxiliaries and water to obtain a pre-coated coating;

[0028] Step b: Mix the pre-made coating and the curing agent to obtain a fire-retardant coating for a nitrogen-bromine organic framework material.

[0029] This invention uses 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 2,5-dibromo-p-phenylenediamine as substrates, and utilizes the reaction of -C=O with -NH2 to prepare a nitrogen-bromine organic framework material with a cyclic structure. The cyclic structure endows the nitrogen-bromine organic framework material with excellent thermal stability, solvent resistance, high shear strength, and nanostructure. Its large specific surface area and the unsaturated bonds in the framework are beneficial for adsorbing combustibles.

[0030] Applying the aforementioned nitrogen-bromine organic framework material to fire-retardant coatings offers several advantages. Firstly, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine has a high nitrogen content, readily forming cyclic structures. The resulting nitrogen-bromine organic framework possesses a cyclic structure, which is beneficial for adsorbing combustibles. In the fire-retardant coating of this invention, pentaerythritol is added to provide a char source, while ammonium polyphosphate and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide promote char formation. Utilizing the porous nature of the nitrogen-bromine organic framework, it serves as the carbon skeleton of the char layer, improving the density and uniformity of the char layer. This is beneficial for insulating heat and combustibles, avoiding the problem of poor consistency in the fire-retardant coating caused by uneven char layer distribution. Simultaneously, the nitrogen-bromine organic framework of this invention has numerous benzene ring structures, which, through the conjugation of electron clouds, form a more stable char layer, improving the impact resistance and service life of the fire-retardant coating.

[0031] On the other hand, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine has a high nitrogen content, and 2,5-dibromo-p-phenylenediamine contains bromine and nitrogen, providing a high content of nitrogen and bromine sources. Bromine is used in flame retardants, decomposing to produce hydrogen bromide. Hydrogen bromide reacts with HO·, a chain reaction active substance in the flame, to eliminate the active free radicals generated by the combustion reaction, thereby slowing down or terminating the chain reaction of combustion and achieving the purpose of flame retardancy. At the same time, nitrogen-based flame retardants easily release ammonia, N2 and other flammable gases after thermal decomposition. The formation of gases and the endothermic reaction of flame retardant conversion bring away most of the heat, reducing the surface temperature of the polymer. It can also react with oxygen in the air to form water and nitrogen oxides. While consuming the oxygen on the surface of the raw materials, it achieves excellent flame retardant effect. However, the hydrogen bromide released by combustion has a certain degree of toxicity. Therefore, the fireproof coating of this invention adds antimony trioxide to inhibit the generation of smoke and reduce the harm of bromine.

[0032] Furthermore, the nitrogen-bromine organic framework of the present invention contains a large number of polar chemical bonds (NO, C-Br, CO), which have good compatibility with waterborne epoxy resins and are suitable for use in waterborne coating systems.

[0033] Therefore, using nitrogen-bromine organic framework materials in conjunction with other flame-retardant additives can improve the fire resistance of epoxy composites and enhance their mechanical properties.

[0034] 3. Beneficial effects

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] (1) In this invention, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 2,5-dibromo-p-phenylenediamine are selected as substrates. The nitrogen-bromine organic framework prepared by reacting -C=O with -NH2 has a cyclic structure, which is beneficial to the adsorption of combustibles.

[0037] (2) The nitrogen-bromine organic framework of the present invention has a large number of benzene ring structures, which form a more stable carbon layer through the conjugation of electron clouds, thereby improving the impact resistance and service life of the material.

[0038] (3) The nitrogen-bromine organic framework of the present invention can be used in fire-retardant coatings as a carbon skeleton of the carbon layer, which can improve the density and uniformity of the carbon layer, which is beneficial to the insulation of heat and combustibles, and improve the flame retardant performance of the coating.

[0039] (4) The nitrogen-bromine organic framework of the present invention contains a large number of polar chemical bonds, which have good compatibility with waterborne epoxy resins and are suitable for waterborne coating systems. Attached Figure Description

[0040] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless specifically indicated, these drawings are intended only to conceptually illustrate the structural construction described herein and are not necessarily drawn to scale.

[0041] Figure 1 This is a schematic diagram of the structure of the nitrogen-bromine organic framework material in Example 1 of the present invention;

[0042] Figure 2 This is a scanning electron microscope image of the fire-retardant coating of Embodiment 1 of the present invention, with a magnification of 20,000.

[0043] Figure 3 This is a macroscopic image of the nitrogen-bromine organic framework material of Example 1 of the present invention;

[0044] Figure 4 This is the TG diagram of the nitrogen-bromine organic framework material in Example 1 of the present invention. Detailed Implementation

[0045] The following detailed description of exemplary embodiments of the invention is taken with reference to the accompanying drawings, which form part of the description and illustrate exemplary embodiments in which the invention may be practiced. While these exemplary embodiments have been described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be implemented and various changes may be made to the invention without departing from the spirit and scope thereof. The more detailed description of embodiments of the invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and not restrictive of the description of the features and characteristics of the invention, to suggest the best mode for carrying out the invention, and is sufficient to enable those skilled in the art to practice the invention. Therefore, the scope of the invention is defined only by the appended claims.

[0046] Example 1

[0047] A fire-retardant coating based on a nitrogen-bromine organic framework material comprises the following components in parts by weight: 100 parts of waterborne epoxy resin, 15 parts of nitrogen-bromine organic framework material, 10 parts of flame retardant additive, 40 parts of curing agent diethylenetriamine, 10 parts of additive, and 10 parts of water.

[0048] The preparation process of the nitrogen-bromine organic framework material includes the following steps:

[0049] Step a, Dissolving: Add 1.0 g of 2,5-dibromo-p-phenylenediamine and 1.5 g of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to 20 mL of toluene, and then sonicate to disperse for 30 min.

[0050] Step b, adding acid: Add 10 mL of nitric acid solution (0.2 mol / L) to the mixed solution obtained in step a, and then sonicate for 30 min;

[0051] Step c, reaction: Transfer the mixture obtained in step b to a reaction vessel and place it in an environment of 150°C for 24 hours;

[0052] Step d: Cooling, centrifuging with toluene, washing three times, and then drying in a 50°C drying oven for 24 hours to obtain nitrogen-bromine organic framework material.

[0053] The flame retardant additive is a mixture of antimony trioxide, ammonium polyphosphate, pentaerythritol, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a mass ratio of 1:2:10:2.

[0054] The additive is fluoroalkyl silicone oil and glass fiber with a length of 0.5-1 cm, with a mass ratio of 1:5.

[0055] The preparation process of the fire-retardant coating based on nitrogen-bromine organic framework materials includes the following steps:

[0056] A pre-formed coating is prepared by mixing waterborne epoxy resin, nitrogen-bromine organic framework material, flame retardant additives, auxiliaries, and water; the pre-formed coating is then mixed with a curing agent, diethylenetriamine, to obtain a fire-retardant coating for the nitrogen-bromine organic framework material.

[0057] The structure and properties of the nitrogen-bromine organic framework material prepared in Example 1 of this invention are as follows: Figure 1-4 As shown, the thermal decomposition temperature of traditional flame retardant materials is generally around 200℃. As can be seen from the TG graph, the nitrogen-bromine organic framework material of Example 1 of this invention does not decompose between 0-300℃, and the decomposition accelerates above 300℃. The mass after 600℃ is the remaining ash, which is about 100℃ higher than the thermal decomposition temperature of traditional flame retardant materials.

[0058] Example 2

[0059] A fire-retardant coating based on a nitrogen-bromine organic framework material is characterized by comprising the following components in parts by weight: 110 parts of waterborne epoxy resin, 23 parts of nitrogen-bromine organic framework material, 16 parts of flame retardant additive, 51 parts of curing agent diethylenetriamine, 12 parts of additive, and 13 parts of water.

[0060] The preparation process of the nitrogen-bromine organic framework material includes the following steps:

[0061] Step a, Dissolving: Add 1.3g of 2,5-dibromo-p-phenylenediamine and 1.6g of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to 20mL of toluene, and then sonicate to disperse for 30min.

[0062] Step b, adding acid: Add 10 mL of nitric acid solution (0.2 mol / L) to the mixed solution obtained in step a, and then sonicate for 30 min;

[0063] Step c, reaction: Transfer the mixture obtained in step b to a reaction vessel and place it in an environment of 150°C for 24 hours;

[0064] Step d: Cooling, centrifuging with toluene, washing three times, and then drying in a 50°C drying oven for 24 hours to obtain nitrogen-bromine organic framework material.

[0065] The flame retardant additive comprises a mixture of antimony trioxide, ammonium polyphosphate, pentaerythritol, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a mass ratio of 1:2:10:2.

[0066] The additives are dimethyl silicone oil and glass fibers with a length of 1-2 cm, with a mass ratio of 1:5.

[0067] The preparation process of the fire-retardant coating based on nitrogen-bromine organic framework materials includes the following steps:

[0068] A pre-formed coating is prepared by mixing waterborne epoxy resin, nitrogen-bromine organic framework material, flame retardant additives, auxiliaries, and water; the pre-formed coating is then mixed with a curing agent, diethylenetriamine, to obtain a fire-retardant coating for the nitrogen-bromine organic framework material.

[0069] Example 3

[0070] A fire-retardant coating based on a nitrogen-bromine organic framework material comprises the following components in parts by weight: 120 parts of waterborne epoxy resin, 30 parts of nitrogen-bromine organic framework material, 20 parts of flame retardant additive, 55 parts of curing agent diethylenetriamine, 15 parts of additive, and 15 parts of water.

[0071] The preparation process of the nitrogen-bromine organic framework material includes the following steps:

[0072] Step a, Dissolving: Add 1.5g of 2,5-dibromo-p-phenylenediamine and 1.9g of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to 20mL of toluene, and then sonicate to disperse for 30min.

[0073] Step b, adding acid: Add 10 mL of nitric acid solution (0.2 mol / L) to the mixed solution obtained in step a, and then sonicate for 30 min;

[0074] Step c, reaction: Transfer the mixture obtained in step b to a reaction vessel and place it in an environment of 160°C for 36 hours;

[0075] Step d: Cooling, centrifuging with toluene, washing three times, and then drying in a 50°C drying oven for 24 hours to obtain nitrogen-bromine organic framework material.

[0076] The flame retardant additive comprises a mixture of antimony trioxide, ammonium polyphosphate, pentaerythritol, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a mass ratio of 1:2:10:2.

[0077] The additive is a long-chain alkyl silicone oil and glass fiber with a length of 2-4 cm, with a mass ratio of 1:5.

[0078] The preparation process of the fire-retardant coating based on nitrogen-bromine organic framework materials includes the following steps:

[0079] A pre-formed coating is prepared by mixing waterborne epoxy resin, nitrogen-bromine organic framework material, flame retardant additives, auxiliaries, and water; the pre-formed coating is then mixed with a curing agent, diethylenetriamine, to obtain a fire-retardant coating for the nitrogen-bromine organic framework material.

[0080] Comparative Example

[0081] The product comprises the following components in parts by weight: 120 parts waterborne epoxy resin, 20 parts ammonium polyphosphate, 55 parts curing agent diethylenetriamine, 15 parts additives, and 15 parts water.

[0082] The additives are polydimethylsiloxane and glass fiber (2 mm in length and 50-150 μm in diameter) in a mass ratio of 1:5.

[0083] The preparation process includes the following steps:

[0084] A pre-coating is prepared by mixing water-based epoxy resin, ammonium polyphosphate, flame retardant additives, auxiliaries, and water; the pre-coating is then mixed with a curing agent, diethylenetriamine, to obtain a fire-retardant coating.

[0085] The parameters of fire-retardant coatings prepared in Examples 1-3 were compared with the requirements of national and industry standards. The following standards were used to measure the performance parameters: impact resistance strength according to GB / T 1732-1993 Test Method for Impact Resistance of Coating Film; maximum heat release rate according to ISO 5660-1 / 2 / 3 / 4-2002; thermal decomposition temperature according to GB / T 27761-2011 National Standard Test Method for Weight Loss and Residue of Thermogravimetric Analyzer.

[0086] The test results are shown in Table 1:

[0087] Table 1 shows the test results of various parameters of the fire-retardant coatings in comparative examples and experimental examples 1-3.

[0088]

[0089] As shown in Table 1, the impact strength, maximum heat release rate, and thermal decomposition temperature of the coatings prepared in Examples 1-3 are all higher than those of the comparative example. This indicates that the fire-retardant coatings prepared by adding nitrogen-bromine organic framework materials in this invention have superior mechanical and flame-retardant properties. The higher thermal decomposition temperature is due to the better flame-retardant properties of the synthesized material, while the higher fracture energy and fracture stress are due to the better compatibility of the added materials with epoxy resin, indicating that the prepared fire-retardant coatings have better mechanical properties.

[0090] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fire-retardant coating, characterized in that, The product comprises, by weight, 100-120 parts of waterborne epoxy resin, 15-30 parts of nitrogen-bromine organic framework material, 10-20 parts of flame retardant additive, 40-55 parts of curing agent, 10-15 parts of auxiliary agent, and 10-15 parts of water. The nitrogen-bromine organic framework material is a cyclic structure prepared from 2,5-dibromo-p-phenylenediamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, with the following structural formula: ； The flame retardant additive is a mixture of antimony trioxide, ammonium polyphosphate, pentaerythritol and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, in a mass ratio of 1:2:10:

2.

2. The fire-retardant coating according to claim 1, characterized in that, The nitrogen-bromine organic framework material has a pore size of 100 nm and a particle size of 1~4 μm.

3. The fire-retardant coating according to claim 1, characterized in that, The preparation method of the nitrogen-bromine organic framework material specifically includes the following steps: Step a, Dissolution: Add 2,5-dibromo-p-phenylenediamine and 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to the solvent and mix thoroughly to obtain a mixed solution; Step b, Add acid: Add acid solution to the mixed solution obtained in step a, and mix well to obtain a mixture; Step c, reaction: The mixture obtained in step b is reacted at a certain temperature; Step d: Cooling, centrifugation, washing three times, and drying to obtain nitrogen-bromine organic framework material.

4. The fire-retardant coating according to claim 3, characterized in that, The mass ratio of 2,5-dibromo-p-phenylenediamine to 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine is (1.0~1.5):(1.5~1.9).

5. The fire-retardant coating according to claim 3, characterized in that, The molar ratio of the acid to 2,5-dibromo-p-phenylenediamine in step b is 1:(1.8~2.9).

6. The fire-retardant coating according to claim 3, characterized in that, In step c, the reaction temperature is 150~160℃ and the reaction time is 24~36h.

7. The fire-retardant coating according to claim 1, characterized in that, The curing agent is one or more of diethylenetriamine, ethylenediamine, and polyamide.

8. The fire-retardant coating according to claim 7, characterized in that, The additive is a mixture of silicone defoamer and glass fiber, wherein the mass ratio of silicone defoamer to glass fiber is 1:5, and the silicone defoamer is one or more of dimethyl silicone oil, fluoroalkyl silicone oil and long-chain alkyl silicone oil; the length of the glass fiber is one or more of 0.5-1cm, 1-2cm and 2-4cm.

9. A process for preparing the fire-retardant coating according to any one of claims 1-8, characterized in that, Includes the following steps: Step a, Premixed coating preparation: Waterborne epoxy resin, nitrogen-bromine organic framework material, flame retardant additives, auxiliaries and water are mixed to obtain a premixed coating; Step b, Preparation of mixed coating: The pre-made coating and curing agent are mixed to obtain a fire-retardant coating of nitrogen-bromine organic framework material.

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