A modified triazine ring-containing flame-retardant polyurea coating, and a preparation method and application thereof

Abstract

The application belongs to the technical field of polymer material modification, and discloses a modified flame-retardant polyurea coating containing a triazine ring as well as a preparation method and application thereof.The modified flame-retardant polyurea coating comprises an A component and a B component; the A component comprises a phosphorus-containing resin with active hydroxyl groups, a hydroxyl-terminated resin, isocyanate, and a plasticizer; and the B component comprises an amine compound containing a triazine ring, an amino chain extender, an amino-terminated resin, a water-removing agent, a catalyst, and a defoaming agent. Through molecular structure design, the triazine ring structure is introduced into the polyurea main chain in the form of a liquid reaction component, and is compounded with the phosphorus-containing resin to construct an efficient phosphorus-nitrogen synergistic flame-retardant system, thereby fundamentally solving the technical problems of poor compatibility, easy agglomeration, and mechanical property degradation of traditional solid flame retardants with the polyurea matrix, and having a wide application prospect in the fields of new energy vehicles, electronic appliances, building protection, and industrial pipelines.

Description

Technical Field

[0001] This invention relates to the field of polymer material modification technology, specifically to a modified flame-retardant polyurea coating containing a triazine ring, its preparation method, and its application. Background Technology

[0002] Polyurea (PUA) is a type of high-molecular-weight elastomer material synthesized from amino and isocyanate components through a stepwise polymerization reaction. Its molecular backbone is characterized by urea bonds (-NH-CO-NH-), allowing for thick-coating application over a wide temperature range. It has been widely used in heavy-duty anti-corrosion coatings, building waterproofing, pipe linings, elastomer flooring, and military protection. However, the polyurea backbone is rich in carbon, hydrogen, and oxygen, with a limiting oxygen index (LOI) typically below 19%, classifying it as a flammable material. When temperatures exceed 250-300°C, the chemical bonds in the polyurea molecular chain break and degrade, releasing large amounts of flammable volatile organic compounds (VOCs), accompanied by severe melting and dripping and the release of large quantities of toxic fumes. This poses a significant threat to human life and property safety, severely restricting its widespread use in critical areas such as building steel structures, rail transportation, ship cabins, and petrochemicals, where strict fire safety requirements exist.

[0003] To improve the flame retardant properties of polyurea materials, the commonly used technical approach is to add flame retardants to the polyurea formulation system for blending modification. Based on their physical form, flame retardants can be divided into two main categories: liquid-based and powder-based flame retardants. Commonly used powder flame retardants include inorganic metal hydrates such as aluminum hydroxide and magnesium hydroxide, as well as phosphorus-nitrogen-based flame retardants such as ammonium polyphosphate (APP), melamine polyphosphate (MPP), and melamine cyanurate (MCA). Liquid flame retardants are represented by organic phosphate esters such as tricresyl phosphate (TCP) and tris(2-chloropropyl) phosphate (TCPP). However, powder flame retardants lack chemical bonding with the polyurea matrix, resulting in weak interfacial adhesion. Furthermore, the high surface energy of the powder particles makes them prone to agglomeration and precipitation during use and storage, making it difficult to achieve uniform and stable dispersion in the polyurea system. This significantly degrades the tensile strength, elongation at break, and impact resistance of the material. As for liquid flame retardants, they are only physically blended with the polyurea matrix. During the application of the coating, flame retardant molecules are prone to migration and precipitation, which leads to a gradual deterioration of the flame retardant effect over time and insufficient flame retardant durability. At the same time, liquid flame retardants only play a plasticizing role in the polyurea system, which will significantly reduce the glass transition temperature and crosslinking density of the coating, thereby impairing the mechanical strength, heat resistance and chemical corrosion resistance of the coating.

[0004] Triazine cyclic compounds have attracted widespread attention in the flame retardant field due to their unique molecular structure. However, currently available commercially available triazine flame retardants are all in solid powder form, and their surface polarity differs significantly from that of the polyurea matrix, resulting in poor compatibility. Direct physical mixing can easily lead to a sharp increase in system viscosity, making it difficult to achieve uniform dispersion. Furthermore, solid particles can easily act as defect sources during coating curing, initiating microcracks and degrading the coating's density and mechanical integrity. In addition, adding large amounts of solid flame retardants can significantly increase the application viscosity of the coating system, affecting spraying performance and even leading to application defects such as uneven coating thickness and poor leveling.

[0005] Therefore, developing a triazine ring reactive flame-retardant modifier with a green and economical synthesis process and good compatibility with polyurea systems, and applying it to the flame-retardant modification of polyurea materials, in order to overcome the technical defects of traditional additive flame retardants and achieve synergistic improvement of flame-retardant performance and mechanical properties, has important academic research value and broad market application prospects. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a modified flame-retardant polyurea coating containing a triazine ring, its preparation method, and its application.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a modified flame-retardant polyurea coating containing a triazine ring, comprising component A and component B; Component A comprises the following components in parts by weight: 5-15 parts of phosphorus-containing resin with active hydroxyl groups, 20-55 parts of hydroxyl-terminated resin, 40-60 parts of isocyanate, and 2-10 parts of plasticizer. Component B comprises the following components in parts by weight: 20-50 parts of a triazine ring-containing amine compound, 5-40 parts of an amino chain extender, 10-70 parts of an amino-terminated resin, 4-10 parts of a dehydrating agent, 0.1-0.5 parts of a catalyst, and 0.1-0.5 parts of a defoamer. The triazine ring-containing amine compound is prepared by a condensation reaction of cyanuric acid and a terminal amino polymer.

[0008] This invention, through molecular structure design, introduces a triazine ring structure into the polyurea backbone as a liquid reactive component, and then combines it with a phosphorus-containing resin to construct a highly efficient phosphorus-nitrogen synergistic flame retardant system. Specifically, this invention prepares a triazine ring-containing amine compound through the condensation reaction of cyanuric acid and an amino-terminated polymer. This compound's molecular structure contains both a triazine ring and an amino-terminated active group. The triazine ring, as the core flame-retardant structure, promotes cross-linking to form char when heated, creating a dense protective layer. The amino-terminated active group allows it to participate as a reactive monomer in the chain extension reaction of polyurea, chemically bonding into the polyurea polymer backbone. This fundamentally avoids the migration and precipitation problems of physically blended flame retardants, endowing the coating with durable and stable flame-retardant properties. Secondly, the phosphorus-containing resin with active hydroxyl groups in component A of this invention not only provides phosphorus elements to form a highly efficient phosphorus-nitrogen synergistic flame retardant effect with nitrogen elements in the triazine ring, significantly improving the flame retardant efficiency of the coating (reaching UL94 V0 level), but the active hydroxyl groups in its molecular structure can also react with isocyanates and be incorporated into the polyurethane / polyurea network in the form of chemical bonds, further enhancing the permanent adhesion of the flame retardant components.

[0009] Therefore, this invention has successfully prepared a modified polyurea coating with both excellent mechanical properties and long-lasting and efficient flame retardant properties through the molecular design of reactive flame retardant monomers, the construction of a phosphorus-nitrogen synergistic flame retardant system, and the precise matching of two-component reactive coating formulations. This solves the technical problem of balancing flame retardant and mechanical properties in traditional polyurea materials. The resulting product has broad application prospects in fields with high requirements for both fire safety and mechanical durability, such as new energy vehicle chassis, battery packs, and electronic equipment protection.

[0010] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, component A comprises the following components in parts by weight: 5-8 parts of phosphorus-containing resin with active hydroxyl groups, 27-40 parts of hydroxyl-terminated resin, 45-58 parts of isocyanate, and 7-10 parts of plasticizer.

[0011] Preferably, component A comprises the following components in parts by weight: 5 parts of phosphorus-containing resin with active hydroxyl groups, 34 parts of hydroxyl-terminated resin, 51 parts of isocyanate, and 10 parts of plasticizer.

[0012] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, component B comprises the following components in parts by weight: 30-40 parts of triazine ring-containing amine compound, 16.5-38.5 parts of amino chain extender, 12.8-38.8 parts of amino-terminated resin, 4-5 parts of dehydrating agent, 0.3-0.4 parts of catalyst, and 0.3-0.5 parts of defoamer.

[0013] Preferably, component B comprises the following components in parts by weight: 40 parts of a triazine ring-containing amine compound, 30.5 parts of an amino chain extender, 21.5 parts of an amino-terminated resin, 5 parts of a dehydrating agent, 0.4 parts of a catalyst, and 0.3 parts of a defoamer.

[0014] In a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, component B further includes 3-5 parts of color paste.

[0015] Preferably, component B further includes 3 parts of color paste.

[0016] In a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the mass ratio of component A to component B is (0.8~1.5):1.

[0017] In the triazine ring-modified flame-retardant polyurea coating of the present invention, when the amounts of components A and B are within the above-mentioned range, the isocyanate groups in component A and the active amino and hydroxyl groups in component B can achieve an ideal stoichiometric balance of reaction, ensuring a moderate crosslinking density, thereby making the coating have better mechanical properties and media resistance.

[0018] Preferably, the mass ratio of component A to component B is 1.1:1.

[0019] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, in component A, the phosphorus-containing resin with active hydroxyl groups includes at least one of N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester and trimethylolphosphine oxide.

[0020] In the triazine ring-modified flame-retardant polyurea coating of the present invention, the phosphorus element in the above-mentioned phosphorus-containing resin molecular structure can generate strong acid substances such as phosphoric acid and polyphosphoric acid during combustion, which promotes the dehydration and char formation of the polyurea matrix. At the same time, it works synergistically with the nitrogen-containing non-combustible gas generated by the decomposition of the triazine ring, exerting flame-retardant effect in both the gas phase and the condensed phase, thus achieving a highly efficient phosphorus-nitrogen synergistic flame-retardant effect.

[0021] Preferably, the phosphorus-containing resin with active hydroxyl groups includes trimethylolphosphine oxide.

[0022] As a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the hydroxyl-terminated resin includes at least one of polyethylene glycol, polytetrahydrofuran glycol, polytrimethylene ether glycol, polycaprolactone glycol, and polycarbonate glycol.

[0023] The hydroxyl-terminated resin of the present invention can provide flexible segments for component A, giving polyurea coatings good elasticity and low-temperature toughness.

[0024] Preferably, the hydroxyl-terminated resin comprises polytrimethylene ether glycol.

[0025] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the isocyanate includes at least one of diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, phenylmethylene diisocyanate, and terephthalic diisocyanate.

[0026] Preferably, the isocyanate includes diphenylmethane diisocyanate and toluene diisocyanate.

[0027] As a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the plasticizer includes at least one of the following: tributyl acetylacetonate, dioctyl terephthalate, dipropylene glycol dibenzoate, and diethylene glycol dibenzoate.

[0028] Preferably, the plasticizer comprises tributyl acetylcitrate.

[0029] In a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the number-average molecular weight of the hydroxyl-terminated resin is 1000 g / mol to 3000 g / mol.

[0030] In the triazine ring-modified flame-retardant polyurea coating of the present invention, the number-average molecular weight of the hydroxyl-terminated resin is controlled within this range, which can provide sufficient flexible chain segment length for the polyurea network, ensuring good elasticity and elongation at break, and also ensure its reactivity and compatibility with isocyanate, avoiding the problem of excessive viscosity and decreased reactivity of the system due to excessively high molecular weight.

[0031] Preferably, the number-average molecular weight of the hydroxyl-terminated resin is 3000 g / mol.

[0032] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the amino chain extender includes at least one of diethyltoluene diamine, dimethylthiotoluene diamine, 4,4'-methylenebis(2-ethyl)aniline, 4,4'-bis-sec-butylaminodiphenylmethane, and 3,3-dimethyl-4,4-diaminodicyclohexylmethane.

[0033] Preferably, the amino chain extender includes diethyltoluenediamine and dimethylthiotoluenediamine.

[0034] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the amino-terminated resin includes at least one of amino-terminated polyethylene oxide ether, amino-terminated polypropylene oxide ether, amino-terminated polytetramethylene ether, polytetramethylene ether diol bis(p-aminobenzoate), and amino-terminated alkyl polysiloxane.

[0035] The amino-terminated resin of the present invention serves as the source of flexible segments in component B, and together with the hydroxyl-terminated resin in component A, it constructs the soft segment structure of polyurea, thereby imparting high elasticity, high elongation at break, and excellent low-temperature performance to the coating.

[0036] Preferably, the amino-terminated resin comprises amino-terminated polyoxypropylene ether.

[0037] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the dehydrating agent includes at least one of molecular sieve, ketimine, aldolimine, and oxazolidine.

[0038] Preferably, the dehydrating agent comprises a molecular sieve.

[0039] As a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the catalyst includes at least one of organotin catalysts and organobismuth catalysts.

[0040] Preferably, the organotin catalyst includes at least one of dibutyltin dilaurate, dibutyltin diacetate, di(dodecyl sulfide)dibutyltin, and stannous octoate.

[0041] Preferably, the organic bismuth catalyst includes at least one of bismuth isooctanoate, bismuth laurate, bismuth neodecanoate, and bismuth naphthenate.

[0042] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the defoamer includes at least one of organosilicon defoamers and polyether defoamers.

[0043] Preferably, the defoamer includes at least one of TEGO Airex 900 from DIGIC, Defom 6800 from Haiming Sterling, AFCONA-2727 from Evcona, BKEPERPOL®-768 from Jintuan Chemical, and BYK-057 from BYK.

[0044] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the terminal amino resin has a functionality of 2 to 3 and a number-average molecular weight of 1000 g / mol to 5000 g / mol.

[0045] Preferably, the terminal amino resin has a functionality of 2 and a number-average molecular weight of 2000 g / mol.

[0046] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the terminal amino polymer includes at least one of terminal amino polyethylene oxide ether, terminal amino polypropylene oxide ether, terminal amino polytetramethylene ether, and terminal aminoalkyl polysiloxane.

[0047] Preferably, the terminal amino polymer comprises terminal amino polyoxypropylene ether.

[0048] As a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the terminal amino polymer has a functionality of 2-3 and a number-average molecular weight of 400 g / mol to 3000 g / mol.

[0049] Preferably, the terminal amino polymer has a functionality of 2 and a number-average molecular weight of 2000 g / mol.

[0050] In a preferred embodiment of the triazine-containing modified flame-retardant polyurea coating of the present invention, the molar ratio of cyanuric acid to the terminal amino polymer is 1:(3~6).

[0051] This invention utilizes the reaction of cyanuric acid with an amino-terminated polymer to precisely control the molar ratio of cyanuric acid to the amino-terminated polymer, successfully designing triazine cyclic amine compounds into a room-temperature liquid state. This allows them to achieve molecular-level uniform mixing with other liquid raw materials in component B, completely avoiding the inherent drawbacks of solid flame retardants in polyurea matrices, such as uneven dispersion, easy agglomeration, and interface defects. This ensures that the final coating has excellent mechanical integrity and impact resistance.

[0052] Preferably, the molar ratio of cyanuric acid to the terminal amino polymer is 1:5.

[0053] As a preferred embodiment of the triazine ring-containing modified flame-retardant polyurea coating of the present invention, the preparation method of the triazine ring amine compound includes the following steps: mixing cyanuric acid and terminal amino polymer evenly, then adding a catalyst, reacting, and obtaining the triazine ring amine compound.

[0054] Preferably, the mixing temperature is 180℃~240℃.

[0055] More preferably, the mixing temperature is 200°C.

[0056] Preferably, the catalyst comprises alumina and / or 5A molecular sieve.

[0057] More preferably, the catalyst comprises alumina.

[0058] Preferably, the mass of the catalyst is 30% to 60% of the mass of the cyanuric acid.

[0059] More preferably, the mass of the catalyst is 34% of the mass of the cyanuric acid.

[0060] Preferably, the reaction temperature is 180℃~240℃ and the time is 1h~6h.

[0061] More preferably, the reaction temperature is 200°C and the reaction time is 5 hours.

[0062] Secondly, the present invention provides a method for preparing the modified flame-retardant polyurea coating containing a triazine ring, comprising the following steps: S1. A phosphorus-containing resin with active hydroxyl groups, a hydroxyl-terminated resin, and a plasticizer are mixed, and after vacuum dehydration, isocyanate is added to react and obtain component A. S2. Mix a triazine ring-containing amine compound, an amino chain extender, and an amino-terminated resin, then add a dehydrating agent, a defoamer, and a catalyst in sequence, and mix thoroughly to obtain component B. S3. Mix the A component and the B component, and cure to obtain the modified flame-retardant polyurea coating containing triazine rings.

[0063] The preparation method of the triazine ring-modified flame-retardant polyurea coating of the present invention is simple, controllable, requires no special equipment, and is suitable for large-scale production.

[0064] In a preferred embodiment of the preparation method of the present invention, in step S1, the reaction temperature is 85℃-90℃ and the time is 2h-4h.

[0065] Preferably, in step S1, the reaction temperature is 90°C and the time is 4 hours.

[0066] In a preferred embodiment of the preparation method of the present invention, in step S3, the mixing is carried out by high-pressure airless spraying.

[0067] Thirdly, the present invention provides the application of the modified flame-retardant polyurea coating containing triazine rings in new energy vehicle chassis, battery packs, roofs, electronic devices, household appliances, industrial pipelines, and heavy machinery.

[0068] The modified flame-retardant polyurea coating containing triazine rings of this invention has excellent mechanical properties, impact resistance and V0 flame retardant effect, and is especially suitable for application scenarios with high requirements for both fire safety and mechanical durability.

[0069] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention synthesizes a reactive amine compound containing a triazine ring through molecular structure design. This compound is chemically bonded to the polyurea polymer backbone, fundamentally solving the problem of traditional physically blended flame retardants easily migrating and precipitating during coating application, leading to insufficient flame retardant durability. This imparts highly efficient and durable flame retardant properties to the polyurea coating. Furthermore, the reaction process only produces water, without the formation of corrosive hydrogen halides or difficult-to-separate salts. The raw materials are inexpensive and readily available, and the synthesis process is low-carbon and environmentally friendly. Secondly, the triazine ring-containing amine compound prepared by reacting a terminal amino polymer with cyanuric acid is a room-temperature liquid. It exhibits excellent compatibility with the polyurea system, achieving uniform dispersion at the molecular level. This completely avoids the mechanical property degradation and coating defects caused by poor compatibility and easy agglomeration of traditional solid flame retardants. Furthermore, the introduction of rigid triazine rings and the increase in crosslinking density in this invention not only do not impair the inherent high elasticity and flexibility of polyurea, but also simultaneously enhance the tensile strength, impact toughness, and surface hardness of the coating through the synergy of intramolecular physical crosslinking points and chemical crosslinking networks. At the same time, the denser crosslinked structure effectively blocks the penetration pathways of corrosive media (water, acid, alkali, salt spray), significantly improving chemical corrosion resistance and achieving multiple synergistic gains in flame retardancy, mechanical properties, and corrosion resistance. In addition, this invention combines triazine ring-containing amine compounds with phosphorus-containing resins in component A to construct a highly efficient phosphorus-nitrogen synergistic flame retardant system. During combustion, the phosphorus component promotes char formation, while the nitrogen component releases non-flammable gases to dilute flammable gases. This synergistic effect allows the coating of this invention to achieve a UL 94V0 flame retardant rating without the need for large amounts of solid flame retardants, maximizing flame retardant efficiency.

[0070] Therefore, this invention, through the molecular design of reactive flame-retardant monomers, the construction of a phosphorus-nitrogen synergistic flame-retardant system, and the precise matching of two-component reactive coating formulations, successfully achieves a synergistic improvement in the flame-retardant and mechanical properties of polyurea materials. Moreover, the preparation method is simple, environmentally friendly, and requires no special equipment to achieve stable production. It provides a reliable technical solution for the large-scale manufacturing of high-performance flame-retardant polyurea coatings and has broad application prospects in fields such as new energy vehicles, electronic appliances, building protection, and industrial pipelines. Detailed Implementation

[0071] To better illustrate the objectives, technical solutions, and advantages of this invention, the invention will be further described below with reference to specific embodiments. Those skilled in the art should understand that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0072] The following description, in conjunction with specific embodiments, illustrates the practical effects of the present invention.

[0073] Unless otherwise specified, the experimental methods used in the examples are conventional methods; the materials, reagents, equipment, etc. used are all commercially available unless otherwise specified.

[0074] The raw materials used in the following embodiments and comparative examples are described below, but are not limited to these materials: Polytetrahydrofuran diol, with a number average molecular weight of 2000 g / mol, was purchased from Hyosung Chemical (Jiaxing) Co., Ltd., model PTMEG2000; Polyethylene glycol, with a number average molecular weight of 1000 g / mol, was purchased from Changhua Chemical Technology Co., Ltd., model CHPEG-1000; Polytrimethylene ether diol, with a number average molecular weight of 2700 g / mol, was purchased from SK Chemicals, South Korea, under the model name ECOTRION H2700. The number-average molecular weight of the polymers described above in this invention was determined by gel permeation chromatography.

[0075] Amino-terminated polytetramethylene ether, with a functionality of 2 and a number-average molecular weight of 2000 g / mol, was purchased from Guangzhou Yinxu Technology Co., Ltd., model YX-THF200. The amino-terminated polyoxypropylene ether, with a functionality of 2 and a number-average molecular weight of 2000 g / mol, was purchased from Zibo Zhengda Polyurethane Co., Ltd., model ZD-1200. The amino-terminated polyoxypropylene ether, with a functionality of 3 and a number-average molecular weight of 5000 g / mol, was purchased from Zibo Zhengda Polyurethane Co., Ltd., model ZT-1500. The terminal aminopropyl polysiloxane, with a functionality of 2 and a number-average molecular weight of 2000 g / mol, was purchased from Shanghai Tiger Polymer Technology Co., Ltd., model number Tech-2420. The number-average molecular weight of the polymers described above in this invention was determined by gel permeation chromatography.

[0076] Molecular sieve, purchased from Shanghai Jiuzhou New Materials Co., Ltd., model JZ-PUB(09); Defoamer BKEPERPOL®-768, purchased from Zhuhai Jintuan Chemical Co., Ltd. The defoamer TEGO Airex 900 was purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd. The colorant is the D series colorant from Shanghai Xiyan Industrial Co., Ltd. (DOTP as carrier).

[0077] Example 1: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which is composed of component A and component B in a mass ratio of 1.1:1; Component A consists of the following components by mass percentage: 8% diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, 27% polytetrahydrofuran glycol (number average molecular weight of 2000 g / mol), 7% dioctyl terephthalate, and 58% diphenylmethane diisocyanate; Component B consists of the following components by mass percentage: 30% triazine ring-containing amine compounds, 28.5% diethyltoluene diamine, 12.8% amino-terminated polytetramethylene ether (functionality 2, number average molecular weight 2000 g / mol), 20% amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol), 5% molecular sieve, 0.4% dibutyltin dilaurate, 0.3% defoamer BKEPERPOL®-768, and 3% colorant; The preparation method of amine compounds containing a triazine ring includes the following steps: Cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to a reaction vessel at a molar ratio of 1:5. The mixture was slowly heated and stirred to make it miscible. Then, the temperature was raised to 200°C, and alumina (34% of the mass of cyanuric acid) was added. The reaction was continued for 5 hours. After the reaction was completed, the temperature was lowered to 100°C, the catalyst was removed by filtration, and the filtrate was distilled under reduced pressure to obtain amine compounds containing triazine rings.

[0078] The preparation method of the triazine-containing modified flame-retardant polyurea coating in this embodiment includes the following steps: (1) Diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, polytetrahydrofurandiol (number average molecular weight of 2000 g / mol) and dioctyl terephthalate were added to a reaction vessel and heated to 100°C for vacuum dehydration for 1 h. After dehydration, the temperature was lowered to 70°C and diphenylmethane diisocyanate was added. The reaction was carried out at 85°C for 3 h to obtain component A. (2) Triazine ring-containing amine compounds, diethyltoluene diamine, amino-terminated polytetramethylene ether (functionality 2, number average molecular weight 2000 g / mol) and amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol) were added to the reaction vessel, stirred evenly, and then molecular sieves were added. After mixing evenly, defoamer BKEPERPOL®-768 and catalyst dibutyltin dilaurate were added. After mixing, the color was adjusted to obtain component B. (3) Mix and spray components A and B at a mass ratio of 1.1:1 using a high-pressure airless spraying device. After curing, a modified flame-retardant polyurea coating containing triazine rings is obtained.

[0079] Example 2: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which is composed of component A and component B in a mass ratio of 1.1:1; Component A consists of the following components by mass percentage: 6% diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, 31% polyethylene glycol (number average molecular weight 1000 g / mol), 8% dioctyl terephthalate, and 55% diphenylmethane diisocyanate; Component B consists of the following components by mass percentage: 35% triazine ring-containing amine compounds, 16.5% diethyltoluene diamine, 10% 4,4'-methylenebis(2-ethyl)aniline, 38.8% amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol), 5% molecular sieve, 0.4% bismuth isooctanoate, 0.3% defoamer TEGO Airex 900, and 4% colorant; The preparation method of amine compounds containing a triazine ring includes the following steps: Cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to a reaction vessel at a molar ratio of 1:6. The mixture was slowly heated and stirred to make it miscible. Then, the temperature was raised to 200°C, and alumina (40% of the mass of cyanuric acid) was added. The reaction was continued for 5 hours. After the reaction was completed, the temperature was lowered to 100°C, the catalyst was removed by suction filtration, and the filtrate was distilled under reduced pressure to obtain amine compounds containing triazine rings.

[0080] The preparation method of the triazine-containing modified flame-retardant polyurea coating in this embodiment includes the following steps: (1) Diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, polyethylene glycol (number average molecular weight of 1000 g / mol) and dioctyl terephthalate were added to a reaction vessel and heated to 105°C for vacuum dehydration for 1 h. After dehydration, the temperature was lowered to 70°C and diphenylmethane diisocyanate was added. The reaction was carried out at 90°C for 2 h to obtain component A. (2) Triazine ring-containing amine compounds, diethyltoluenediamine, 4,4'-methylenebis(2-ethyl)aniline and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to the reaction vessel, stirred evenly, molecular sieves were added, and after mixing evenly, defoamer TEGO Airex 900 and catalyst bismuth isooctanoate were added, and after mixing, the color was adjusted to obtain component B; (3) Mix and spray components A and B at a mass ratio of 1.1:1 using a high-pressure airless spraying device. After curing, a modified flame-retardant polyurea coating containing triazine rings is obtained.

[0081] Example 3: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which is composed of component A and component B in a mass ratio of 1.1:1; Component A consists of the following components by mass percentage: 6% diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, 31% polyethylene glycol (number average molecular weight 1000 g / mol), 8% dioctyl terephthalate, and 55% diphenylmethane diisocyanate; Component B consists of the following components by mass percentage: 40% triazine ring-containing amine compounds, 24.5% diethyltoluene diamine, 26.7% amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol), 4% aldehyde imine, 0.3% dibutyltin diacetate, 0.5% defoamer BKEPERPOL®-768, and 4% colorant; The preparation method of amine compounds containing a triazine ring includes the following steps: Cyanuric acid and terminal aminopropyl polysiloxane (functionality 2, number average molecular weight 2000 g / mol) were added to a reaction vessel at a molar ratio of 1:5. The mixture was slowly heated and stirred to make it miscible. Then, the temperature was raised to 220°C, and 5A molecular sieve with a mass of 40% of the cyanuric acid mass was added. The reaction was continued for 4 hours. After the reaction was completed, the temperature was lowered to 110°C, the catalyst was removed by suction filtration, and the filtrate was distilled under reduced pressure to obtain amine compounds containing triazine rings.

[0082] The preparation method of the triazine-containing modified flame-retardant polyurea coating in this embodiment includes the following steps: (1) Diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, polyethylene glycol (number average molecular weight of 1000 g / mol) and dioctyl terephthalate were added to a reaction vessel and heated to 105°C for vacuum dehydration for 1 h. After dehydration, the temperature was lowered to 70°C and diphenylmethane diisocyanate was added. The reaction was carried out at 90°C for 2 h to obtain component A. (2) Add the triazine ring-containing amine compound, diethyltoluene diamine and amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol) to the reaction vessel, stir evenly, add aldiamine, mix evenly, then add defoamer BKEPERPOL®-768 and catalyst dibutyltin diacetate, mix and adjust the color to obtain component B; (3) Mix and spray components A and B at a mass ratio of 1.1:1 using a high-pressure airless spraying device. After curing, a modified flame-retardant polyurea coating containing triazine rings is obtained.

[0083] Example 4: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which is composed of component A and component B in a mass ratio of 1.1:1; Component A consists of the following components by mass percentage: 5% trimethylolphosphine oxide, 40% polytrimethylene ether diol (number average molecular weight of 2700 g / mol), 10% tributyl acetylacetonate, and 45% toluene diisocyanate; Component B consists of the following components by mass percentage: 40% triazine ring-containing amine compounds, 21.5% amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol), 20.5% diethyltoluene diamine, 10% dimethylthiotoluene diamine, 5% molecular sieve, 0.4% bismuth isooctanoate, 0.3% defoamer BKEPERPOL®-768, and 3% colorant; The preparation method of amine compounds containing a triazine ring includes the following steps: Cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to a reaction vessel at a molar ratio of 1:5. The mixture was slowly heated and stirred to make it miscible. Then, the temperature was raised to 200°C, and alumina (34% of the mass of cyanuric acid) was added. The reaction was continued for 5 hours. After the reaction was completed, the temperature was lowered to 100°C, the catalyst was removed by filtration, and the filtrate was distilled under reduced pressure to obtain amine compounds containing triazine rings.

[0084] The preparation method of the triazine-containing modified flame-retardant polyurea coating in this embodiment includes the following steps: (1) Tris(hydroxymethyl)phosphine oxide, polytrimethylene ether diol (number average molecular weight of 2700 g / mol) and tributyl acetyl citrate were added to the reaction vessel and heated to 100°C for vacuum dehydration for 1 h. After dehydration, the temperature was lowered to 75°C and toluene diisocyanate was added. The reaction was carried out at 90°C for 4 h to obtain component A. (2) Triazine ring-containing amine compounds, diethyltoluenediamine, dimethylthiotoluenediamine and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to the reaction vessel, stirred evenly, molecular sieves were added, mixed evenly, and then defoamer BKEPERPOL®-768 and catalyst bismuth isooctanoate were added. After mixing, the color was adjusted to obtain component B. (3) Mix and spray components A and B at a mass ratio of 1.1:1 using a high-pressure airless spraying device. After curing, a modified flame-retardant polyurea coating containing triazine rings is obtained.

[0085] Example 5: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which is composed of component A and component B in a mass ratio of 1.1:1; Component A consists of the following components by mass percentage: 5% trimethylolphosphine oxide, 34% polytrimethylene ether diol (number average molecular weight 2700 g / mol), 10% tributyl acetylacetonate, 31% toluene diisocyanate, and 20% diphenylmethane diisocyanate. Component B consists of the following components by mass percentage: 40% triazine ring-containing amine compounds, 21.5% amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol), 20.5% diethyltoluene diamine, 10% dimethylthiotoluene diamine, 5% molecular sieve, 0.4% bismuth isooctanoate, 0.3% defoamer BKEPERPOL®-768, and 3% colorant; The preparation method of amine compounds containing a triazine ring includes the following steps: Cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to a reaction vessel at a molar ratio of 1:5. The mixture was slowly heated and stirred to make it miscible. Then, the temperature was raised to 200°C, and alumina (34% of the mass of cyanuric acid) was added. The reaction was continued for 5 hours. After the reaction was completed, the temperature was lowered to 100°C, the catalyst was removed by filtration, and the filtrate was distilled under reduced pressure to obtain amine compounds containing triazine rings.

[0086] The preparation method of the triazine-containing modified flame-retardant polyurea coating in this embodiment includes the following steps: (1) Tris(hydroxymethyl)phosphine oxide, polytrimethylene ether diol (number average molecular weight of 2700 g / mol), and tributyl acetyl citrate were added to the reaction vessel and heated to 100°C for vacuum dehydration for 1 h. After dehydration, the temperature was lowered to 75°C, toluene diisocyanate and diphenylmethane diisocyanate were added, and the mixture was reacted at 90°C for 4 h to obtain component A. (2) Triazine ring-containing amine compounds, diethyltoluenediamine, dimethylthiotoluenediamine and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) were added to the reaction vessel, stirred evenly, molecular sieves were added, mixed evenly, and then defoamer BKEPERPOL®-768 and catalyst bismuth isooctanoate were added. After mixing, the color was adjusted to obtain component B. (3) Mix and spray components A and B at a mass ratio of 1.1:1 using a high-pressure airless spraying device. After curing, a modified flame-retardant polyurea coating containing triazine rings is obtained.

[0087] Example 6: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which differs from Example 1 only in that: Component A consists of the following components by mass percentage: 5% diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, 43% polytetrahydrofuran glycol (number average molecular weight of 2000 g / mol), 2% dioctyl terephthalate, and 50% diphenylmethane diisocyanate; Component B consists of the following components by mass percentage: 20% triazine ring-containing amine compounds, 5% diethyltoluene diamine, 30.8% amino-terminated polytetramethylene ether (functionality 2, number average molecular weight 2000 g / mol), 36% amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol), 4% molecular sieve, 0.1% dibutyltin dilaurate, 0.1% defoamer BKEPERPOL®-768, and 4% colorant; The remaining components, proportions, and preparation methods are the same as in Example 1.

[0088] Example 7: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which differs from Example 1 only in that: Component A consists of the following components by mass percentage: 15% diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate, 20% polytetrahydrofuran glycol (number average molecular weight 2000 g / mol), 5% dioctyl terephthalate, and 60% diphenylmethane diisocyanate; Component B consists of the following components by mass percentage: 50% triazine ring-containing amine compounds, 35% diethyltoluene diamine, 5% amino-terminated polytetramethylene ether (functionality 2, number average molecular weight 2000 g / mol), 5% amino-terminated polyoxypropylene ether (functionality 3, number average molecular weight 5000 g / mol), 4.2% molecular sieve, 0.3% dibutyltin dilaurate, and 0.5% defoamer BKEPERPOL®-768; The remaining components, proportions, and preparation methods are the same as in Example 1.

[0089] Example 8: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which differs from Example 1 only in that: In the preparation method of amine compounds containing triazine rings, the molar ratio of cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) is 1:4. The remaining components, proportions, and preparation methods are the same as in Example 1.

[0090] Example 9: This embodiment provides a modified flame-retardant polyurea coating containing a triazine ring, which differs from Example 1 only in that: In the preparation method of amine compounds containing triazine rings, the molar ratio of cyanuric acid and amino-terminated polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) is 1:3. The remaining components, proportions, and preparation methods are the same as in Example 1.

[0091] Comparative Example 1: This comparative example provides a modified flame-retardant polyurea coating, which differs from Example 1 only in that: In component B, the triazine ring-containing amine compound is replaced with an equal mass of melamine; The remaining components, proportions, and preparation methods are the same as in Example 1.

[0092] Comparative Example 2: This comparative example provides a modified flame-retardant polyurea coating, which differs from Example 1 only in that: In the preparation method of amine compounds containing triazine rings, terminal amino polyoxypropylene ether (functionality 2, number average molecular weight 2000 g / mol) is replaced with an equimolar amount of p-phenylenediamine; The remaining components, proportions, and preparation methods are the same as in Example 1.

[0093] Comparative Example 3: This comparative example provides a modified flame-retardant polyurea coating, which differs from Example 1 only in that: In component B, the mass percentage of triazine ring-containing amine compounds is 0, and the mass percentage of amino-terminated polytetramethylene ether (functionality 2, number average molecular weight 2000 g / mol) is 42.8%. The remaining components, proportions, and preparation methods are the same as in Example 1.

[0094] Comparative Example 4: This comparative example provides a modified flame-retardant polyurea coating, which differs from Example 1 only in that: In component A, the mass percentage of diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate is 0, and the mass percentage of polytetrahydrofuran glycol (number average molecular weight of 2000 g / mol) is 35%. The remaining components, proportions, and preparation methods are the same as in Example 1.

[0095] Test example: This test case tested the relevant properties of the modified flame-retardant polyurea coatings in the above embodiments and comparative examples. The test results are summarized in Table 1.

[0096] (1) Tensile property test: Test method: The test shall be conducted in accordance with the method 9.2.1 of GB / T 16777-2008, with a tensile speed of 500±50 mm / min, and the tensile strength and elongation at break shall be recorded.

[0097] (2) Tear strength test: Test method: The test shall be conducted in accordance with the method for right-angled specimens in GB / T 529-2008, 5.1.2, without cutting, and the tensile speed shall be 500±50 mm / min.

[0098] (3) Impact resistance test: Test method: The impact resistance of the sample is tested using a drop hammer impact device. A steel ball with a diameter of 30 mm is used to impact the sample with an energy of 150 J, and the surface of the sample is observed to see if cracks or damage occur.

[0099] (4) Flame retardant performance test: Test method: The test shall be conducted in accordance with the UL 94 vertical burning test method. The longitudinal axis of the sample shall be kept perpendicular and the sample shall be burned vertically in the thickness direction. The flame retardancy rating of the sample shall be recorded.

[0100] Table 1: Performance test results of the modified flame-retardant sprayed polyurea materials of the embodiments and comparative examples of the present invention As can be seen from the results in Table 1, the triazine ring-modified flame-retardant polyurea coatings of the present invention exhibit excellent performance in terms of tensile strength, elongation at break, tear strength, and impact resistance, while all achieving the UL 94 V0 flame retardant rating, thus achieving a synergistic improvement in mechanical properties and flame retardant performance. Specifically, Examples 4 and 5, using a trimethylolphosphine oxide compounded isocyanate system, achieved tensile strengths of 26.4 MPa and 26.8 MPa, respectively, and tear strengths of 136 N / mm and 125 N / mm, respectively, demonstrating higher structural rigidity. Examples 1 to 3, while maintaining the V0 flame retardant rating, all exhibited elongation at break exceeding 450%, demonstrating good flexibility and elasticity.

[0101] In contrast, while Comparative Example 1, using melamine as a flame retardant, enabled the polyurea material to achieve a V0 flame retardant rating, melamine, being a solid powder, has high polarity and poor compatibility with the polyurea matrix. This leads to its tendency to agglomerate in the coating, forming microscopic defects that cause cracks when subjected to external impact. Furthermore, it significantly reduces the tensile strength and tear strength of the flame-retardant polyurea material. Additionally, solid flame retardants are prone to precipitation during storage and transportation, causing system inhomogeneity and further affecting the coating's mechanical properties and flame retardant stability. Comparative Example 2, using phenylenediamine instead of amino-terminated polyethers to prepare triazine rings... Amine compounds are solids and difficult to completely dissolve in polyurea systems. After curing, the coating also has microscopic defects, resulting in a significant decrease in mechanical properties and impact resistance. Component B of Comparative Example 3 does not contain triazine cyclic amine compounds. Its system only contains phosphorus-containing flame retardants, which cannot form a phosphorus-nitrogen synergistic flame retardant effect. The flame retardant rating drops to V1, and the tensile strength and tear strength are also reduced. Component A of Comparative Example 4 does not contain phosphorus-containing flame retardants. Although its tensile strength and tear strength are improved, it lacks a phosphorus-nitrogen synergistic flame retardant system, and its flame retardant rating is only V2, with a significant decrease in flame retardant effect.

[0102] In summary, the triazine ring-modified flame-retardant polyurea coating of this invention introduces a triazine ring skeleton and reactive amino-terminated polyether segments through molecular structure design, and, in conjunction with the synergistic effect of the phosphate ester flame-retardant polyol in component A, constructs a highly efficient phosphorus-nitrogen synergistic flame-retardant system. Furthermore, by replacing traditional solid flame-retardant fillers with liquid reactive flame-retardant components, the compatibility and dispersibility issues are fundamentally solved. The resulting coating possesses excellent mechanical properties, impact resistance, and V0-level flame-retardant effect, and has broad application prospects in fields with high requirements for both fire safety and mechanical durability, such as building protection, transportation, chemical corrosion protection, and power equipment.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A modified flame-retardant polyurea coating containing a triazine ring, characterized in that, Includes component A and component B; Component A comprises the following components in parts by weight: 5-15 parts of phosphorus-containing resin with active hydroxyl groups, 20-55 parts of hydroxyl-terminated resin, 40-60 parts of isocyanate, and 2-10 parts of plasticizer. Component B comprises the following components in parts by weight: 20-50 parts of a triazine ring-containing amine compound, 5-40 parts of an amino chain extender, 10-70 parts of an amino-terminated resin, 4-10 parts of a dehydrating agent, 0.1-0.5 parts of a catalyst, and 0.1-0.5 parts of a defoamer. The triazine ring-containing amine compound is prepared by a condensation reaction of cyanuric acid and a terminal amino polymer.

2. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, The mass ratio of component A to component B is (0.8~1.5):

1.

3. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, In component A, the phosphorus-containing resin with active hydroxyl groups includes at least one of N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester and trimethylolphosphine oxide; and / or, the hydroxyl-terminated resin includes at least one of polyethylene glycol, polytetrahydrofuran glycol, polytrimethylene ether glycol, polycaprolactone glycol, and polycarbonate glycol; and / or, the isocyanate includes at least one of diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, phenylmethylene diisocyanate, and terephthalic diisocyanate; and / or, the plasticizer includes at least one of acetylated tributyl citrate, dioctyl terephthalate, dipropylene glycol dibenzoate, and diethylene glycol dibenzoate.

4. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, The number-average molecular weight of the hydroxyl-terminated resin is 1000 g / mol to 3000 g / mol.

5. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, In component B, the amino chain extender includes at least one of diethyltoluenediamine, dimethylthiotoluenediamine, 4,4'-methylenebis(2-ethyl)aniline, 4,4'-bis-sec-butylaminodiphenylmethane, and 3,3-dimethyl-4,4-diaminodicyclohexylmethane; and / or, the amino-terminated resin includes at least one of amino-terminated polyethylene oxide ether, amino-terminated polypropylene oxide ether, amino-terminated polytetramethylene ether, polytetramethylene ether diol bis(p-aminobenzoate), and amino-terminated alkyl polysiloxane; and / or, the dehydrating agent includes at least one of molecular sieve, ketimine, aldolimine, and oxazolidine; and / or, the catalyst includes at least one of organotin catalyst and organobismuth catalyst; and / or, the defoamer includes at least one of organosilicon defoamer and polyether defoamer.

6. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, The terminal amino resin has a functionality of 2 to 3 and a number-average molecular weight of 1000 g / mol to 5000 g / mol.

7. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, The amino-terminated polymer includes at least one of amino-terminated polyoxyethylene ether, amino-terminated polyoxypropylene ether, amino-terminated polytetramethylene ether, and amino-terminated alkyl polysiloxane.

8. The triazine-containing modified flame-retardant polyurea coating as described in claim 1, characterized in that, The molar ratio of cyanuric acid to the terminal amino polymer is 1:(3~6).

9. A method for preparing the triazine-containing modified flame-retardant polyurea coating according to any one of claims 1-8, characterized in that, Includes the following steps: S1. A phosphorus-containing resin with active hydroxyl groups, a hydroxyl-terminated resin, and a plasticizer are mixed, and after vacuum dehydration, isocyanate is added to react and obtain component A. S2. Mix a triazine ring-containing amine compound, an amino chain extender, and an amino-terminated resin, then add a dehydrating agent, a defoamer, and a catalyst in sequence, and mix thoroughly to obtain component B. S3. Mix the A component and the B component, and cure to obtain the modified flame-retardant polyurea coating containing triazine rings.

10. The application of the triazine ring-containing modified flame-retardant polyurea coating according to any one of claims 1-8 in new energy vehicle chassis, battery packs, roofs, electronic devices, household appliances, industrial pipelines, and heavy machinery.

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