Intumescent fireproof coating and application thereof

Abstract

The invention provides an intumescent fire retardant coating and application thereof, and belongs to the technical field of fire retardant coatings. According to the fireproof coating disclosed by the invention, the phosphorus-containing epoxy resin and the organic silicon modified acrylic resin are taken as matrix resin, and the amino silane coupling agent is taken as a main curing agent, so that a cross-linked reticular macromolecular structure of the epoxy resin, the organic silicon modified acrylic resin and the organic silicon resin is formed; through the combined action of various components, the fireproof performance, the damp-heat resistance, the aging resistance, the salt spray corrosion resistance and the mechanical property of the intumescent fireproof coating are improved.

Description

Technical Field

[0001] This disclosure relates to the field of fire-retardant coating technology, specifically to an intumescent fire-retardant coating and its application. Background Technology

[0002] With the development of the new energy vehicle industry, the market is pursuing power batteries with higher energy density and longer driving range; however, this brings the risk of thermal runaway of power batteries leading to fire and explosion.

[0003] Intumescent fire-retardant coatings are one of the methods used by companies worldwide to prevent the spread of fire after thermal runaway of power batteries. The main idea is to apply the intumescent fire-retardant coating to the battery casing and cover. When the battery experiences thermal runaway, it rapidly expands and foams to form a flame-retardant and heat-insulating carbon layer, preventing heat and high-temperature electrolyte from burning the casing and causing it to rupture, leading to combustion and explosion, thus providing valuable escape time for drivers and passengers.

[0004] Currently, most intumescent fire-retardant coatings on the market are products developed by foreign companies in recent years, with major suppliers including PPG, Sika, and Jotun. These products are very expensive. They typically have a viscosity greater than 10,000 mcP.s and often contain mineral fibers, requiring specialized foreign equipment for spraying. Therefore, application tools are very expensive, and the construction cost of spraying production lines for new energy battery packs is also extremely high. With the development of the new energy vehicle industry, the regional and environmental differences and diversity of fire-retardant coating applications are becoming increasingly prominent. The damp heat resistance and weather resistance of solvent-based and solvent-free epoxy fire-retardant coatings on the market are insufficient to meet the requirements of power batteries. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an intumescent fire-retardant coating and its application.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: an intumescent fire-retardant coating is provided, comprising a base material and a curing agent. The base material comprises the following components in parts by weight: 10-30 parts of phosphorus-containing epoxy resin, 15-27 parts of organosilicon-modified acrylic resin, 10-25 parts of ammonium polyphosphate, 5-10 parts of melamine, 5-15 parts of ammonium pentaborate tetrahydrate, 5-15 parts of pigments and fillers, and 0.5-5 parts of additives. The curing agent comprises the following components in parts by weight: 5-20 parts of aminosilane coupling agent and 0.1-1 parts of organotin catalyst.

[0007] In one embodiment, the mass ratio of the phosphorus-containing epoxy resin to the organosilicon-modified acrylic resin is 1:1.2-2.2.

[0008] In one embodiment, the silicone-modified acrylic resin has a viscosity of 100-190 cP at 25°C and a solid content of 48-52%.

[0009] In one embodiment, the aminosilane coupling agent is γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane.

[0010] In one embodiment, the mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 10-16, preferably, the mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 12-14.

[0011] In one embodiment, the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 10-20:6:11; preferably, the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 12-18:6:11.

[0012] In one embodiment, the degree of polymerization of the ammonium polyphosphate is ≥1000.

[0013] In one embodiment, the additive is at least one of a dispersant, a wetting agent, and a defoamer.

[0014] In one embodiment, the organotin catalyst is at least one of dibutyltin dilaurate and dibutyltin diacetate.

[0015] In one embodiment, the pigment or filler is at least one of titanium dioxide, carbon black, barium sulfate, quartz powder, mica powder, feldspar powder, silica fume, calcined porcelain clay, calcined kaolin, silica fume, hollow microspheres, and expanded perlite.

[0016] On the other hand, the use of the intumescent fire-retardant coating in structural fire protection is provided.

[0017] A product comprising a substrate and a coating formed by applying the intumescent fire retardant coating onto the substrate.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention uses phosphorus-containing epoxy resin and organosilicon-modified acrylic resin as matrix resins. The aminosilane coupling agent in the curing agent can cure with the phosphorus-containing epoxy resin crosslinking agent. The organotin catalyst in the curing agent promotes the crosslinking and curing of organosilicon-modified acrylic resin, forming a crosslinked network polymer structure of epoxy resin, organosilicon-modified acrylic resin and organosilicon resin. Ammonium polyphosphate and melamine form a thermally expanding system. Ammonium pentaborate tetrahydrate plays a role in fire prevention and smoke suppression, reducing the smoke flux when the fireproof coating foams under heat. The combined effect of multiple components mainly improves the fire resistance, damp heat resistance and aging resistance of the intumescent fireproof coating, while also improving the salt spray corrosion resistance and mechanical properties to a certain extent. Detailed Implementation

[0019] The advantages and features of this disclosure, as well as the methods for achieving said advantages and features, will be more readily understood by referring to the following detailed description of embodiments. However, this disclosure may be implemented in various other forms and should not be construed as limited to the embodiments set forth herein. The embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art.

[0020] The terminology used in this specification is intended to describe certain embodiments only and should in no way limit this disclosure. Unless expressly used otherwise, singular expressions include the meaning of plural expressions.

[0021] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Any term defined in a comprehensive dictionary shall be interpreted as having the same meaning in the context of the relevant field and, unless expressly defined otherwise, shall not be interpreted as having an idealistic or overly formalistic meaning.

[0022] In order to solve the problem of poor resistance to damp heat and weathering of existing intumescent fire-retardant coatings.

[0023] This disclosure provides an intumescent fire-retardant coating, comprising a base material and a curing agent. The base material comprises the following components in parts by weight: 10-30 parts of phosphorus-containing epoxy resin, 15-27 parts of silicone-modified acrylic resin, 10-25 parts of ammonium polyphosphate, 5-10 parts of melamine, 5-15 parts of ammonium pentaborate tetrahydrate, 5-15 parts of pigments and fillers, and 0.5-5 parts of additives. The curing agent comprises the following components in parts by weight: 5-20 parts of aminosilane coupling agent and 0.1-1 parts of organotin catalyst.

[0024] This disclosure uses phosphorus-containing epoxy resin and silicone-modified acrylic resin as the base resin. The aminosilane coupling agent in the curing agent can cure with the phosphorus-containing epoxy resin crosslinking agent. The organotin catalyst in the curing agent promotes the crosslinking and curing of the silicone-modified acrylic resin, forming a crosslinking system of epoxy resin, silicone-modified acrylic resin and silicone resin. The epoxy resin, silicone-modified acrylic resin and silicone resin work together to form a network polymer structure. Ammonium polyphosphate and melamine form a thermally expanding system. Ammonium pentaborate tetrahydrate plays a role in fire prevention and smoke suppression, reducing the smoke flux when the fireproof coating foams under heat. The combined effect of multiple components improves the fire resistance, damp heat resistance, aging resistance, salt spray corrosion resistance and mechanical properties of the intumescent fireproof coating. Among them, the phosphorus-containing groups in phosphorus-containing epoxy resin can improve the fire resistance of fire-retardant coatings, while also improving their insulation and adhesion. On the one hand, the organosilicon-modified acrylic resin increases the softening point of the fire-retardant coating, making it less prone to softening and melting when heated, reducing the risk of the coating dripping into the electrolyte during thermal runaway. In addition, the fire-retardant coating does not require the addition of mineral fibers to prevent dripping, significantly reducing the difficulty of spraying and avoiding production line shutdowns caused by mineral fiber clogging of automated spraying equipment. Furthermore, because the fire-retardant coating does not contain mineral fibers, the resulting coating has low viscosity, eliminating the need for dilution with volatile solvents during spraying and reducing VOCs generated during construction. On the other hand, the synergistic effect of organosilicon-modified acrylic resin and organosilicon resin improves the fire-retardant coating's resistance to damp heat and weathering.

[0025] Specifically, the weight parts of the phosphorus-containing epoxy resin can be 10 parts, 12 parts, 15 parts, 17 parts, 20 parts, 23 parts, 25 parts, 28 parts, or 30 parts, but are not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0026] Specifically, the weight parts of the organosilicon-modified acrylic resin can be 15 parts, 17 parts, 19 parts, 21 parts, 23 parts, 25 parts, or 27 parts, but are not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0027] Specifically, the ammonium polyphosphate may be in the following weight proportions: 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, 20 parts, 23 parts, or 25 parts, but is not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0028] Specifically, the melamine may be in parts by weight of 5, 6, 7, 8, 9, or 10, but is not limited to the resins listed. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0029] Specifically, the weight parts of the ammonium pentaborate tetrahydrate can be 5 parts, 7 parts, 9 parts, 11 parts, 13 parts, or 15 parts, but are not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0030] Specifically, the weight parts of the pigments and fillers can be 5 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts, or 15 parts, but are not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0031] Specifically, the weight parts of the additive can be 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, or 5 parts, but are not limited to the listed resins. Other unlisted values ​​within the scope of this disclosure are also applicable.

[0032] In one embodiment, the mass ratio of the phosphorus-containing epoxy resin to the silicone-modified acrylic resin is 1:1.2-2.2, for example, it can be 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.1, or 1:2.2, but is not limited to the listed resins. Other unlisted values ​​within this range are also applicable.

[0033] In this disclosure, the mass ratio of phosphorus-containing epoxy resin to silicone-modified acrylic resin affects the fire-retardant coating's resistance to damp heat, heat aging, and toughness. If the mass ratio of phosphorus-containing epoxy resin to silicone-modified acrylic resin is too high, the toughness and resistance to damp heat of the fire-retardant coating will decrease significantly. If the mass ratio of phosphorus-containing epoxy resin to silicone-modified acrylic resin is too low, the heat aging and resistance to damp heat of the fire-retardant coating will decrease significantly.

[0034] In one embodiment, the viscosity of the silicone-modified acrylic resin at 25°C is 100-190 cP, for example, but not limited to 100 cP, 120 cP, 140 cP, 160 cP, 180 cP, or 190 cP; and the solid content is 48-52%, for example, but not limited to 48%, 49%, 50%, 51%, or 52%.

[0035] In this disclosure, the silicone-modified acrylic resin within the above-mentioned scope can further improve the overall performance of fire-retardant coatings.

[0036] Specifically, the solid content of the organosilicon-modified acrylic resin is obtained by testing according to the following method, the specific steps of which are as follows: 1. Weigh the sample and record its mass; 2. Dissolve the sample in dry chloroform and shake at 40°C for 2 hours; 3. Place the sample in a sealed desiccator to remove air bubbles; 4. Weigh the sample and record its mass; 5. Calculate the solid content based on the initial mass and the mass after dissolution of the sample according to the following formula: Solid content = (mass after dissolution - initial mass) / initial mass × 100%.

[0037] Specific examples of silicone-modified acrylic resins include Dow Chemical's DOW DOWSIL™ 805 silicone-modified acrylic resin or Vipaitin GT-406A resin.

[0038] In one embodiment, the phosphorus-containing epoxy resin is obtained by reacting an epoxy resin with a phosphorus-containing compound having active hydrogen groups.

[0039] Specifically, there are no particular restrictions on the epoxy resin as long as it is a known epoxy resin, but it is preferred to be an epoxy resin with an average of 1-4 epoxy groups in the molecule, and more preferably an epoxy resin with 2 epoxy groups. If there is less than 1 epoxy group, the functional groups will decrease and no polymerization will occur when reacting with phosphorus-containing compounds, resulting in a certain degree of decrease in the adhesion and fire resistance of the fire-retardant coating; if there are more than 4 epoxy groups, gelation will occur during the reaction, and even if gelation does not occur, it will lead to an increase in the viscosity of the phosphorus-containing epoxy resin, which in turn increases the viscosity of the fire-retardant coating and increases the difficulty of spraying the fire-retardant coating.

[0040] Specifically, the epoxy equivalent of the epoxy resin is 172-179 g / eq, for example, but not limited to 172 g / eq, 173 g / eq, 174 g / eq, 175 g / eq, 176 g / eq, 177 g / eq, 178 g / eq or 179 g / eq; and the viscosity at 25°C is 10000-25000 cP, for example, but not limited to 10000 cP, 12000 cP, 14000 cP, 15000 cP, 17000 cP, 19000 cP, 20000 cP, 23000 cP or 25000 cP.

[0041] Specifically, the epoxy equivalent of the epoxy resin is obtained according to JIS K 7236 testing.

[0042] Specific examples of epoxy resins include Dow Chemical's DOW DEN-331 phenolic epoxy resin and Yueyang Baling Petrochemical's EP-128 bisphenol A type epoxy resin.

[0043] Specific examples of phosphorus-containing compounds with active hydrogen groups include phosphoric acid and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

[0044] The preparation method of phosphorus-containing epoxy resin can use the well-known preparation method of epoxy resin, that is, to carry out the reaction by stirring at a reaction temperature of 60-200℃.

[0045] Phosphorus-containing epoxy resin and phosphorus-containing compounds with active hydrogen groups can be added to the reaction vessel simultaneously for reaction, or the phosphorus-containing compounds with active hydrogen groups can be added in several batches for reaction.

[0046] A catalyst may also be used in the reaction as needed. The catalyst can be any known and commonly used catalyst in the manufacture of epoxy resins. Examples of usable catalysts include, but are not limited to, triphenylphosphine, tetramethylammonium chloride, and tetraethylammonium bromide, etc., used in amounts of 0.005-1 wt% of the total amount of phosphorus-containing compounds with active hydrogen groups.

[0047] As a reaction solvent, there are no particular restrictions as long as it is non-reactive. Examples include isopropanol, benzene, toluene, xylene, ethylbenzene, acetone, methyl ethyl ketone, methyl butyl ketone, diacetone, cyclopentanone, cyclohexanone, dialkyl ethers, 2-ethoxyethyl ethyl ether, ethanol, 2-butoxyethanol, glycol ethers, propylene glycol monomethyl ether, and dioxane. These reaction solvents can be used alone or in combination. Preferably, the amount of these reaction solvents used is less than 50% of the total mass of the reactants.

[0048] In this disclosure, specific examples of aminosilane coupling agents include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane.

[0049] In one embodiment, the aminosilane coupling agent is γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane.

[0050] In this disclosure, compared with the addition of an aminosilane coupling agent, when the aminosilane coupling agent is γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane, the resulting fire-retardant coating exhibits significantly increased resistance to damp heat and heat aging.

[0051] Specifically, the mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 10-16, for example, but not limited to 10, 11, 12, 13, 14, 15, 16, preferably 12-14; within the above mass ratio range, the resulting fire-retardant coating exhibits significantly increased resistance to damp heat and heat aging.

[0052] In one embodiment, the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 10-20:6:11, for example, but not limited to 12:6:11, 13:6:11, 14:6:11, 15:6:11, 16:6:11, 17:6:11, 18:6:11, preferably 12-18:6:11; within the above mass ratio range, the fire-retardant performance of the obtained fire-retardant coating is further increased.

[0053] In one embodiment, the degree of polymerization of the ammonium polyphosphate is ≥1000, for example, but not limited to 1000, 1100, 1200, 1300, 1500, 1800, 2000, 2500, 2800, or 3000.

[0054] Specifically, the degree of polymerization of the ammonium polyphosphate is obtained according to the standard HG / T 2770-2020 Industrial Ammonium Polyphosphate - Determination of Average Degree of Polymerization (End-Group Titration Method).

[0055] Specific examples of ammonium polyphosphate include Clariant Exolit AP 428 and Shandong Changsheng Flame Retardant New Material Co., Ltd.'s CS-FR APP 342.

[0056] Specific examples of ammonium pentaborate tetrahydrate include Henan Jijia Chemical's ammonium pentaborate tetrahydrate and Shouguang Puer Chemical's ammonium pentaborate tetrahydrate.

[0057] In one embodiment, the additive is at least one of a dispersant, a wetting agent, and a defoamer.

[0058] Dispersants can establish pseudoplasticity, improve the thixotropic flowability of fire-retardant coatings, and prevent sedimentation and sagging; a specific example of a dispersant is BYK-410 from BYK Chemicals in Germany.

[0059] Specifically, the defoamer is a polysiloxane defoamer, which can suppress and effectively inhibit bubbles generated during the preparation and application of fire-retardant coatings; as a specific example of a polysiloxane defoamer, Evonik TEGOAirex 900 can be cited.

[0060] Specifically, examples of organotin catalysts include dibutyltin dilaurate and dibutyltin diacetate.

[0061] In one embodiment, the pigment or filler is at least one of titanium dioxide, carbon black, barium sulfate, quartz powder, mica powder, feldspar powder, silica fume, calcined porcelain clay, calcined kaolin, silica fume, hollow microspheres, and expanded perlite.

[0062] Specifically, titanium dioxide can significantly improve the fire resistance limit of fire-retardant coatings. Specific examples of titanium dioxide include DuPont 706 titanium dioxide and CNNC titanium dioxide R-213.

[0063] Intumescent fire retardant coatings can be prepared using known methods for preparing intumescent fire retardant coatings, namely, by preparing the base material and the curing agent separately, and then mixing the base material and the curing agent evenly before use.

[0064] On the other hand, the use of the intumescent fire-retardant coating in structural fire protection is provided.

[0065] A product comprising a substrate and a coating formed by applying the intumescent fire retardant coating onto the substrate, such as a battery casing, cover plate, or steel structure.

[0066] The intumescent fire-retardant coating disclosed herein can be applied to a variety of substrates, and is particularly suitable for application to metal substrates. To apply the intumescent fire-retardant coating, conventional methods such as spraying, spin coating, or troweling can be used.

[0067] The invention will be described with reference to the following examples. These are for illustrative purposes and should not be construed as limiting the scope of the invention.

[0068] The raw materials used in the embodiments and comparative examples are described below, but are not limited to these materials: The phosphorus-containing epoxy resin was prepared in-house. The preparation method was as follows: 78 parts by weight of epoxy resin (Dow Chemical DOW DEN-331 phenolic epoxy resin, epoxy equivalent of 172-190 g / eq) and 13 parts by weight of isopropanol were mixed evenly and heated to 60°C. Then, 9 parts by weight of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide were added, and the temperature was raised to 85°C. The reaction was carried out for 6 hours to obtain the phosphorus-containing epoxy resin.

[0069] Organosilicon-modified acrylic resin: DOW DOWSIL TM805, purchased from Dow Chemical; Ammonium polyphosphate 1: CS-FR APP 342, degree of polymerization n≧1000, purchased from Shandong Changsheng Flame Retardant New Materials Co., Ltd.; Ammonium polyphosphate 2: Clariant Exolit AP 428, degree of polymerization n≧1000, purchased from Shanghai Kaiyin Chemical Co., Ltd.; Melamine: Purchased from Wujiang Sanyuan Fine Chemical Co., Ltd.; Ammonium pentaborate tetrahydrate: purchased from Shandong Shouguang Puer Chemical Co., Ltd.; Titanium dioxide: Titanium dioxide R-213, purchased from Shanghai Kaiyin Chemical Co., Ltd.; Dispersant: Modified urea solution, BYK-410, purchased from BYK Chemicals, Germany; Defoamer: Polysiloxane defoamer, TEGO Airex 900, purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd.; Silane coupling agent 1: γ-aminopropyltriethoxysilane, KH-550, commercially available; Silane coupling agent 2: γ-aminopropyltrimethoxysilane, KH-540, commercially available; Silane coupling agent 3: N-methyl-3-aminopropyltrimethoxysilane, commercially available; m-Phenylenediamine: Commercially available; Organotin catalyst 1: Dibutyltin dilaurate T-12, purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd.; Organotin catalyst 2: dibutyltin diacetate, purchased from Hubei Xinyuhong Biomedical Technology Co., Ltd.

[0070] Examples and Comparative Examples The composition of the intumescent fire-retardant coatings described in the examples and comparative examples is shown in Tables 1 and 2; the preparation method includes the following steps: Preparation of base material: Add phosphorus-containing epoxy resin and organosilicon-modified acrylic resin to a disperser in proportion and disperse at 500 r / min for 20 min. Then add ammonium polyphosphate, melamine, ammonium pentaborate tetrahydrate, pigments, fillers and additives, and disperse at 900 r / min for 40 min to obtain the base material. Preparation of curing agent: Add aminosilane coupling agent and organotin catalyst to a disperser in proportion and disperse at 300 r / min for 30 min to obtain curing agent; When using, mix the base material and the curing agent evenly to obtain an intumescent fire-retardant coating.

[0071] Table 1 Table 2 Performance testing The intumescent fire-retardant coatings obtained in the examples and comparative examples were subjected to performance tests. The test performance and methods are shown in Table 3, and the test results are shown in Table 4.

[0072] Table 3 Table 4 As shown in Table 4, the adhesion of the intumescent fire-retardant coating disclosed herein is 1.85-3.86 MPa, the fire-retardant time is 62-120 min, the damp heat resistance time is 870-1400 h, the salt spray corrosion resistance time is 893-1400 h, the high and low temperature impact time is 704-1000 h, and the impact height is 25-42 cm. This indicates that the intumescent fire-retardant coating disclosed herein has good fire resistance, damp heat resistance, aging resistance, salt spray corrosion resistance, and mechanical properties.

[0073] Comparative examples 3-7 show that when the mass ratio of phosphorus-containing epoxy resin to silicone-modified acrylic resin is 1:1.2-2.2, the resulting intumescent fire-retardant coating exhibits a damp heat resistance time of 1316-1344 hours, a fire resistance time of 105-120 minutes, and a hydrochloric acid corrosion resistance time of 1180-1200 hours. This indicates that when the mass ratio of phosphorus-containing epoxy resin to silicone-modified acrylic resin is 1:1.2-2.2, the resulting intumescent fire-retardant coating possesses good fire resistance and damp heat resistance.

[0074] Comparing Examples 5 and 8-10, it can be seen that when the aminosilane coupling agent is at least two of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and N-methyl-3-aminopropyltrimethoxysilane, the resulting intumescent fire-retardant coating has a damp heat resistance time of 1280-1344 h and a fire resistance time of 120 min. This indicates that when the aminosilane coupling agent is at least two of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and N-methyl-3-aminopropyltrimethoxysilane, the resulting intumescent fire-retardant coating has better fire resistance and damp heat resistance.

[0075] Comparing Examples 5 and 11-13, it can be seen that when the mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 12-14, the resulting intumescent fire retardant coating has a damp heat resistance time of 1128-1344 h, a fire resistance time of 97-120 min, and a hydrochloric acid corrosion resistance time of 1040-1200 h. This indicates that when the mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 12-14, the resulting intumescent fire retardant coating has better fire resistance, damp heat resistance, and hydrochloric acid corrosion resistance.

[0076] Comparing Examples 5 and 14-17, it can be seen that when the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 12-18:6:11, the fire retardant time of the obtained intumescent fire retardant coating is 98-120 min, and the damp heat resistance time is 1175-1344 h. This indicates that when the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 12-18:6:11, the obtained intumescent fire retardant coating has good fire retardant performance and damp heat resistance.

[0077] Based on Comparative Example 2, except for the absence of m-phenylenediamine, the remaining components and dosages were the same. The resulting intumescent fire retardant coating could not be cured, meaning that the resulting intumescent fire retardant coating could not be tested for the above performance.

[0078] Finally, it should be noted that the above embodiments are used to illustrate the technical solutions of the present invention and not 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. An intumescent fire-retardant coating, characterized in that, The product includes a base material and a curing agent. The base material comprises the following components in parts by weight: 10-30 parts of phosphorus-containing epoxy resin, 15-27 parts of silicone-modified acrylic resin, 10-25 parts of ammonium polyphosphate, 5-10 parts of melamine, 5-15 parts of ammonium pentaborate tetrahydrate, 5-15 parts of pigments and fillers, and 0.5-5 parts of additives. The curing agent comprises the following components in parts by weight: 5-20 parts of aminosilane coupling agent and 0.1-1 parts of organotin catalyst.

2. The intumescent fire-retardant coating as described in claim 1, characterized in that, The mass ratio of the phosphorus-containing epoxy resin and the organosilicon-modified acrylic resin is 1:1.2-2.

2.

3. The intumescent fire-retardant coating as described in claim 1, characterized in that, In one embodiment, the silicone-modified acrylic resin has a viscosity of 100-190 cP at 25°C and a solid content of 48-52%.

4. The intumescent fire-retardant coating as described in claim 1, characterized in that, The aminosilane coupling agent is γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane.

5. The intumescent fire-retardant coating as described in claim 4, characterized in that, The mass ratio of γ-aminopropyltriethoxysilane to γ-aminopropyltrimethoxysilane is 10-16, preferably 12-14.

6. The intumescent fire-retardant coating as described in claim 1, characterized in that, The mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 10-20:6:11; preferably, the mass ratio of ammonium polyphosphate, melamine, and ammonium pentaborate tetrahydrate is ammonium polyphosphate:melamine:ammonium pentaborate tetrahydrate = 12-18:6:

11.

7. The intumescent fire-retardant coating as described in claim 1, characterized in that, The degree of polymerization of the ammonium polyphosphate is ≥1000.

8. The intumescent fire-retardant coating as described in claim 1, characterized in that, The additive is at least one of dispersant, wetting agent and defoamer; And / or, the organotin catalyst is at least one of dibutyltin dilaurate and dibutyltin diacetate; And / or, the pigments and fillers are at least one of titanium dioxide, carbon black, barium sulfate, quartz powder, mica powder, feldspar powder, silica fume, calcined kaolin, calcined kaolin, silica powder, hollow microspheres, and expanded perlite.

9. The use of the intumescent fire-retardant coating as described in any one of claims 1-8 in fire protection of structures.

10. A product comprising a substrate and a coating formed by applying an intumescent fire retardant coating as described in any one of claims 1-8 onto the substrate.

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