Environment-friendly flame-retardant waterproof coating and preparation method thereof

Abstract

The present application relates to a kind of green environmental protection fire-retardant waterproof coating and its preparation method, waterproof coating is calculated according to weight fraction, including: 80-120 parts water-based epoxy resin emulsion, 36-58 parts fire-retardant filler, 1-3 parts dispersing agent, 0.2-2 parts defoaming agent, 0.5-1.5 parts leveling agent, 40-60 parts water-based curing agent and 35-55 parts deionized water.The present application is prepared by modifying treatment to ammonium polyphosphate, then titanium disilicide powder is prepared with titanium disilicide powder.Fire-retardant titanium disilicide powder is used as fire retardant and filler in the present application, not only greatly improve the fire resistance of coating, but also enhance the impact resistance and bonding properties of coating.

Description

Technical Field

[0001] This invention relates to the field of green coatings, specifically to a green, environmentally friendly, flame-retardant, and waterproof coating and its preparation method. Background Technology

[0002] With the continuous improvement of the national environmental protection system and the deepening of people's environmental awareness, environmentally friendly coatings are bound to become the general trend. Solvent-based or oil-based coatings have a strong pungent odor and are flammable and explosive. If handled carelessly during construction and transportation, the consequences could be disastrous. Moreover, traditional coatings are relatively simple and lack comprehensive functions. In contrast, green and environmentally friendly coatings are non-toxic, harmless, do not pollute the environment, and do not harm human health.

[0003] In existing technologies, flame-retardant small-molecule organic and inorganic substances, such as magnesium hydroxide, calcium hydroxide, and ammonium polyphosphate, are typically added to improve the flame-retardant properties of water-based coatings. While these small-molecule materials can reduce the flammability of the coating, compatibility issues cause them to easily leach from the paint film during use in humid environments. Over time, this leads to a sharp decline in the coating's fire resistance. Furthermore, some flame retardants, such as DOPO and phosphates, hydrolyze in the presence of water. This not only reduces the flame-retardant properties of the coating but also causes the hydrolysis products to react with the coating film, reducing its performance and affecting its subsequent use. Summary of the Invention

[0004] To address the problems existing in the prior art, the purpose of this invention is to provide a green, environmentally friendly, flame-retardant waterproof coating and its preparation method.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] In a first aspect, the present invention provides a green and environmentally friendly flame-retardant waterproof coating, comprising, by weight parts:

[0007] 80-120 parts waterborne epoxy resin emulsion, 36-58 parts flame retardant filler, 1-3 parts dispersant, 0.2-2 parts defoamer, 0.5-1.5 parts leveling agent, 40-60 parts waterborne curing agent, and 35-55 parts deionized water.

[0008] Preferably, the aqueous epoxy resin emulsion is YPE-20WE0254, manufactured by Shanghai Yuanbang Resin Manufacturing Co., Ltd., with a solid content of 52±2%, an epoxy equivalent of 500-540 g / mol, and a rotor viscosity of 1000-5000 cp / (30℃, 30 rpm).

[0009] Preferably, the dispersant is BYK-180.

[0010] Preferably, the defoamer is an organosilicon defoamer BYK-024.

[0011] Preferably, the leveling agent is BYK-333.

[0012] Preferably, the water-based curing agent is a water-soluble modified polyamide epoxy curing agent, model AB-HGC-W60, manufactured by Zhejiang Anbang New Material Development Co., Ltd.

[0013] Preferably, the flame-retardant filler is flame-retardant titanium disilicide powder, and the preparation method includes:

[0014] S1. Weigh 2,5-bis(aminomethyl)furan and ammonium polyphosphate and reflux them in an aqueous solution of ethanol to prepare modified ammonium polyphosphate.

[0015] S2. Weigh titanium disilicide powder and heat-treat it in an alkaline solution to prepare purified titanium disilicide powder.

[0016] S3. The purified titanium disilicide powder was reacted with γ-glycidyl etheroxypropyltrimethoxysilane in an aqueous solution by heating to prepare epoxy titanium disilicide powder.

[0017] S4. Epoxy-based titanium disilicide powder and modified ammonium polyphosphate are mixed in an organic solvent and then heated to react, thus preparing flame-retardant titanium disilicide powder.

[0018] Preferably, step S1 specifically includes:

[0019] S1. Weigh out ethanol and deionized water, mix them evenly, and transfer them to a reflux condenser. Inert gas is introduced as a protective gas. 2,5-Di(aminomethyl)furan and ammonium polyphosphate are added in sequence. Under stirring, the temperature is gradually raised to reflux and the reaction is maintained at reflux for 3-6 hours. The solvent is removed by filtration, and the mixture is washed three times with anhydrous ethanol. After drying, modified ammonium polyphosphate is obtained.

[0020] More preferably, in S1, the mass ratio of 2,5-bis(aminomethyl)furan, ammonium polyphosphate, ethanol and deionized water is 1.26-1.58:2.5-3:30-50:1-5.

[0021] More preferably, in S1, the degree of polymerization of ammonium polyphosphate is 50-100 g / mol.

[0022] Preferably, step S2 specifically includes:

[0023] S2. Weigh titanium disilicide powder and place it in sodium hydroxide solution. After ultrasonic homogenization, pour it into a flask and stir at 40-50℃ for 1-3 hours. Then, centrifuge to collect the solid product, wash it with distilled water until neutral, and dry it in an oven to obtain purified titanium disilicide powder.

[0024] More preferably, in S2, the particle size of the titanium disilicide powder is 50-100 μm, and the molar concentration of the sodium hydroxide solution is 0.05-0.5 mol / L.

[0025] More preferably, in S2, the mass ratio of titanium disilicide powder to sodium hydroxide solution is 1:15-25.

[0026] Preferably, step S3 specifically includes:

[0027] S3. The purified titanium disilicide powder was mixed with γ-glycidyl etheroxypropyltrimethoxysilane in deionized water, heated to 50-60℃, stirred for 6-10 h, centrifuged to collect the solid product, washed three times with distilled water, and dried in an oven to obtain epoxy titanium disilicide powder.

[0028] More preferably, in step S3, the mass ratio of purified titanium disilicide powder, γ-glycidyl etheroxypropyltrimethoxysilane, and deionized water is 1:0.21-0.3:10-20.

[0029] Preferably, step S4 specifically includes:

[0030] S4. Disperse epoxy-based titanium disilicide powder in N,N-dimethylformamide, homogenize it under ultrasonication, then add modified ammonium polyphosphate, introduce an inert gas as a protective gas, stir evenly at room temperature, then heat to 60-70℃, stir and react for 2-6 hours, centrifuge to collect the solid product, wash it three times with distilled water, and dry it to obtain flame-retardant titanium disilicide powder.

[0031] More preferably, in S4, the mass ratio of epoxy-based titanium disilicide powder, modified ammonium polyphosphate, and N,N-dimethylformamide is 1:0.42-0.56:15-25.

[0032] Secondly, the present invention provides a method for preparing a green, environmentally friendly, flame-retardant, and waterproof coating, comprising:

[0033] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0034] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0035] The beneficial effects of this invention are as follows:

[0036] 1. Ammonium polyphosphate (APP), as a flame retardant containing both nitrogen and phosphorus, has the advantages of low smoke, low toxicity, and good thermal stability. However, when used in water-based coatings, it is easily affected by the external environment and may precipitate. To address this, this invention modifies ammonium polyphosphate and then combines it with titanium disilicide powder to prepare flame-retardant titanium disilicide powder. In this invention, the flame-retardant titanium disilicide powder serves as both a flame retardant and a filler, significantly improving the flame retardancy of the coating and enhancing its impact resistance and adhesion properties, thus meeting the requirements of standard GB 12441-2018 "Decorative Fire Retardant Coatings".

[0037] 2. The preparation principle of the flame-retardant titanium disilicide powder of the present invention is as follows: First, 2,5-di(aminomethyl)furan containing furan groups and diamino groups undergoes an ion exchange reaction with ammonium polyphosphate in an ethanol solution. One amino group of 2,5-di(aminomethyl)furan is fixed on the surface of ammonium polyphosphate, thereby obtaining 2,5-di(aminomethyl)furan-modified ammonium polyphosphate. Then, the purified titanium disilicide powder is surface-treated with an epoxy coupling agent (γ-glycidyl etheroxypropyltrimethoxysilane) to obtain titanium disilicide powder containing epoxy groups. Then, the epoxy disilicide powder and the modified ammonium polyphosphate are mixed and thermally reacted in an organic solvent. By utilizing the combination reaction between epoxy groups and amino groups, the modified ammonium polyphosphate is fixed on the surface of the titanium disilicide powder, and finally, flame-retardant titanium disilicide powder is obtained.

[0038] 3. In the process of preparing flame-retardant titanium disilicide powder in this invention, the titanium disilicide powder is purified by heat treatment with sodium hydroxide solution, which not only purifies the powder but also further activates its surface.

[0039] 4. In the process of preparing flame-retardant titanium disilicide powder, the present invention introduces a furan compound containing amino groups into ammonium polyphosphate, which increases the molecular weight and nitrogen content. At the same time, the thermal stability and good char-forming properties of the furan group also enhance the flame-retardant properties of ammonium polyphosphate.

[0040] 5. In the process of preparing flame-retardant titanium disilicide powder according to the present invention, ammonium polyphosphate is fixed on the surface of titanium disilicide via 2,5-bis(aminomethyl)furan linkage. The surface of titanium disilicide is first modified with epoxy groups, and then cross-linked with modified ammonium polyphosphate containing amino groups to form a network structure that coats the surface of titanium disilicide. During this process, the modified ammonium polyphosphate is also wrapped on the surface of titanium disilicide along with the network structure, thereby making the expandable carbon layer more continuous and dense, thus improving its flame retardancy.

[0041] 6. The flame-retardant titanium disilicide powder prepared by this invention contains abundant organic active groups, which is more conducive to its bonding with water-based epoxy resin emulsion, thereby making the flame-retardant filler more uniform and stable in dispersion, and enhancing the mechanical properties, heat resistance and water resistance of the coating. Detailed Implementation

[0042] To more clearly illustrate the present invention and to gain a clearer understanding of its technical features, objectives, and beneficial effects, the technical solution of the present invention will now be described in detail below, but this should not be construed as limiting the scope of the present invention.

[0043] The present invention will be further described below with reference to the following embodiments.

[0044] Example 1

[0045] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0046] 100 parts waterborne epoxy resin emulsion YPE-20WE0254, 42 parts flame-retardant titanium disilicide powder, 2 parts dispersant BYK-180, 1.2 parts silicone defoamer BYK-024, 1 part leveling agent BYK-333, 50 parts waterborne curing agent AB-HGC-W60 and 45 parts deionized water.

[0047] The preparation method of the flame-retardant titanium disilicide powder includes:

[0048] S1. Weigh out ethanol and deionized water, mix them evenly, and transfer them to a reflux condenser. Inert gas is introduced as a protective gas. 2,5-Di(aminomethyl)furan and ammonium polyphosphate with a degree of polymerization of 80 g / mol are added in sequence. Under stirring, the temperature is gradually raised to reflux and the reaction is maintained at reflux for 5 hours. The solvent is removed by filtration, and the mixture is washed three times with anhydrous ethanol. After drying, the modified ammonium polyphosphate is obtained.

[0049] The mass ratio of 2,5-bis(aminomethyl)furan, ammonium polyphosphate, ethanol and deionized water is 1.34:2.8:40:3.

[0050] S2. Weigh titanium disilicide powder with a particle size of 60 μm and place it in 0.1 mol / L sodium hydroxide solution. After ultrasonic homogenization, pour it into a flask and stir at 45 °C for 2 h. Then, centrifuge to collect the solid product, wash it with distilled water until neutral, and dry it in an oven to obtain purified titanium disilicide powder.

[0051] The mass ratio of titanium disilicide powder to sodium hydroxide solution is 1:20.

[0052] S3. The purified titanium disilicide powder was mixed with γ-glycidyl etheroxypropyltrimethoxysilane in deionized water, heated to 55°C, stirred for 8 hours, centrifuged to collect the solid product, washed three times with distilled water, and dried in an oven to obtain epoxy titanium disilicide powder.

[0053] The mass ratio of purified titanium disilicide powder, γ-glycidyl etheroxypropyltrimethoxysilane, and deionized water is 1:0.26:15.

[0054] S4. Disperse epoxy disilicide powder in N,N-dimethylformamide, homogenize it under ultrasonic action, then add modified ammonium polyphosphate, introduce inert gas as protective gas, stir evenly at room temperature, heat to 65℃, stir and react for 4 hours, centrifuge to collect solid product, wash three times with distilled water, dry and obtain flame retardant disilicide powder.

[0055] The mass ratio of epoxy-based titanium disilicide powder, modified ammonium polyphosphate, and N,N-dimethylformamide is 1:0.48:20.

[0056] The preparation method of the above-mentioned green and environmentally friendly flame-retardant waterproof coating includes:

[0057] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0058] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0059] Example 2

[0060] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0061] 80 parts of waterborne epoxy resin emulsion YPE-20WE0254, 36 parts of flame-retardant titanium disilicide powder, 1 part of dispersant BYK-180, 0.2 parts of silicone defoamer BYK-024, 0.5 parts of leveling agent BYK-333, 40 parts of waterborne curing agent AB-HGC-W60 and 35 parts of deionized water.

[0062] The preparation method of the flame-retardant titanium disilicide powder includes:

[0063] S1. Weigh out ethanol and deionized water, mix them evenly, and transfer them to a reflux condenser. Inert gas is introduced as a protective gas. 2,5-Di(aminomethyl)furan and ammonium polyphosphate with a degree of polymerization of 50 g / mol are added in sequence. Under stirring, the temperature is gradually raised to reflux and the reaction is maintained at reflux for 3 hours. The solvent is removed by filtration, and the mixture is washed three times with anhydrous ethanol. After drying, the modified ammonium polyphosphate is obtained.

[0064] The mass ratio of 2,5-bis(aminomethyl)furan, ammonium polyphosphate, ethanol, and deionized water is 1.26:2.5:30:1.

[0065] S2. Weigh titanium disilicide powder with a particle size of 50 μm and place it in a 0.05 mol / L sodium hydroxide solution. After ultrasonic homogenization, pour it into a flask and stir at 40 °C for 1 h. Then, centrifuge to collect the solid product, wash it with distilled water until neutral, and dry it in an oven to obtain purified titanium disilicide powder.

[0066] The mass ratio of titanium disilicide powder to sodium hydroxide solution is 1:15-25.

[0067] S3. The purified titanium disilicide powder was mixed with γ-glycidyl etheroxypropyltrimethoxysilane in deionized water, heated to 50°C, stirred for 6 hours, centrifuged to collect the solid product, washed three times with distilled water, and dried in an oven to obtain epoxy titanium disilicide powder.

[0068] The mass ratio of purified titanium disilicide powder, γ-glycidyl etheroxypropyltrimethoxysilane, and deionized water is 1:0.21:10.

[0069] S4. Disperse epoxy-based titanium disilicide powder in N,N-dimethylformamide, homogenize it under ultrasonication, then add modified ammonium polyphosphate, introduce an inert gas as a protective gas, stir evenly at room temperature, heat to 60℃, stir and react for 2 hours, collect the solid product by centrifugation, wash three times with distilled water, and dry to obtain flame-retardant titanium disilicide powder.

[0070] The mass ratio of epoxy-based titanium disilicide powder, modified ammonium polyphosphate, and N,N-dimethylformamide is 1:0.42:15.

[0071] The preparation method of the above-mentioned green and environmentally friendly flame-retardant waterproof coating includes:

[0072] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0073] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0074] Example 3

[0075] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0076] 120 parts waterborne epoxy resin emulsion YPE-20WE0254, 58 parts flame-retardant titanium disilicide powder, 3 parts dispersant BYK-180, 2 parts silicone defoamer BYK-024, 1.5 parts leveling agent BYK-333, 60 parts waterborne curing agent AB-HGC-W60 and 55 parts deionized water.

[0077] The preparation method of the flame-retardant titanium disilicide powder includes:

[0078] S1. Weigh out ethanol and deionized water, mix them evenly, and transfer them to a reflux condenser. Inert gas is introduced as a protective gas. 2,5-Di(aminomethyl)furan and ammonium polyphosphate with a degree of polymerization of 100 g / mol are added in sequence. Under stirring, the temperature is gradually raised to reflux and the reaction is maintained at reflux for 6 hours. The solvent is removed by filtration, and the mixture is washed three times with anhydrous ethanol. After drying, the modified ammonium polyphosphate is obtained.

[0079] The mass ratio of 2,5-bis(aminomethyl)furan, ammonium polyphosphate, ethanol and deionized water is 1.58:3:50:5.

[0080] S2. Weigh titanium disilicide powder with a particle size of 100 μm and place it in a 0.5 mol / L sodium hydroxide solution. After ultrasonic homogenization, pour it into a flask and stir at 50 °C for 3 h. Then, centrifuge to collect the solid product, wash it with distilled water until neutral, and dry it in an oven to obtain purified titanium disilicide powder.

[0081] The mass ratio of titanium disilicide powder to sodium hydroxide solution is 1:25.

[0082] S3. The purified titanium disilicide powder was mixed with γ-glycidyl etheroxypropyltrimethoxysilane in deionized water, heated to 60°C, stirred for 10 h, centrifuged to collect the solid product, washed three times with distilled water, and dried in an oven to obtain epoxy titanium disilicide powder.

[0083] The mass ratio of purified titanium disilicide powder, γ-glycidyl etheroxypropyltrimethoxysilane, and deionized water is 1:0.3:20.

[0084] S4. Disperse epoxy disilicide powder in N,N-dimethylformamide, homogenize it under ultrasonication, then add modified ammonium polyphosphate, introduce inert gas as a protective gas, stir evenly at room temperature, heat to 70℃, stir and react for 6 hours, collect the solid product by centrifugation, wash three times with distilled water, and dry to obtain flame-retardant disilicide powder.

[0085] The mass ratio of epoxy-based titanium disilicide powder, modified ammonium polyphosphate, and N,N-dimethylformamide is 1:0.56:25.

[0086] The preparation method of the above-mentioned green and environmentally friendly flame-retardant waterproof coating includes:

[0087] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0088] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0089] Example 4

[0090] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0091] 90 parts waterborne epoxy resin emulsion YPE-20WE0254, 50 parts flame-retardant titanium disilicide powder, 1.5 parts dispersant BYK-180, 1.4 parts silicone defoamer BYK-024, 0.8 parts leveling agent BYK-333, 45 parts waterborne curing agent AB-HGC-W60 and 40 parts deionized water.

[0092] The preparation method of flame-retardant titanium disilicide powder is the same as that in Example 1.

[0093] The preparation method of the above-mentioned green and environmentally friendly flame-retardant waterproof coating includes:

[0094] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0095] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0096] Example 5

[0097] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0098] 110 parts waterborne epoxy resin emulsion YPE-20WE0254, 54 parts flame-retardant titanium disilicide powder, 2.2 parts dispersant BYK-180, 1.6 parts silicone defoamer BYK-024, 1.2 parts leveling agent BYK-333, 55 parts waterborne curing agent AB-HGC-W60 and 50 parts deionized water.

[0099] The preparation method of flame-retardant titanium disilicide powder is the same as that in Example 1.

[0100] The preparation method of the above-mentioned green and environmentally friendly flame-retardant waterproof coating includes:

[0101] (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained.

[0102] (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.

[0103] Comparative Example 1

[0104] The difference from Example 1 is that the flame-retardant titanium disilicide powder is replaced with ordinary titanium disilicide.

[0105] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0106] 100 parts waterborne epoxy resin emulsion YPE-20WE0254, 42 parts titanium disilicide powder, 2 parts dispersant BYK-180, 1.2 parts silicone defoamer BYK-024, 1 part leveling agent BYK-333, 50 parts waterborne curing agent AB-HGC-W60 and 45 parts deionized water.

[0107] The preparation method of the waterproof coating is the same as that in Example 1.

[0108] Comparative Example 2

[0109] The difference from Example 1 is that the flame-retardant titanium disilicide powder is replaced with a mixture of ammonium polyphosphate and ordinary titanium disilicide, wherein the mass ratio of ammonium polyphosphate to ordinary titanium disilicide is 0.48:1.

[0110] A green, environmentally friendly, flame-retardant, and waterproof coating, comprising, by weight:

[0111] 100 parts waterborne epoxy resin emulsion YPE-20WE0254, 28.4 parts titanium disilicide powder, 13.6 parts ammonium polyphosphate, 2 parts dispersant BYK-180, 1.2 parts silicone defoamer BYK-024, 1 part leveling agent BYK-333, 50 parts waterborne curing agent AB-HGC-W60 and 45 parts deionized water.

[0112] The preparation method of the waterproof coating is the same as that in Example 1.

[0113] Experimental Example

[0114] The performance of the waterproof coatings prepared in Examples 1, 4-5, and Comparative Examples 1-2 was tested. The drying conditions for the waterproof coatings were: surface drying at room temperature followed by 24 hours of standing at room temperature. The tests were conducted primarily according to the standards GB 12441-2018 "Decorative Fire-Retardant Coatings," and the test results are shown in Table 1.

[0115] Table 1 Flame retardant performance of different coatings

[0116] Technical indicators Example 1 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Adhesion (Grade) ≤3 0 1 1 2 2 Flexibility (mm) ≤3 1 1 1 2 3 Impact resistance (cm) ≥20 ＞50 ＞50 ＞50 40 30 Water resistance (h) ＞24 satisfy satisfy satisfy satisfy satisfy Resistance to damp heat (h) ＞48 satisfy satisfy satisfy satisfy Not satisfied Flame resistance time (min) ≥15 34 37 40 / 22 Flame retardancy test * satisfy satisfy satisfy / Not satisfied Mass loss (g) ≤5.0 2.4 2.1 2.0 / 4.7 <![CDATA[Carbonized volume (cm 3 )]]> ≤25 9 9 8 / 17

[0117] * in Table 1 indicates that the average remaining length of the test specimen after combustion should be >150mm, and no test specimen should have a remaining length of zero after combustion; the average flue gas temperature measured by thermocouples in each group of tests should not exceed 200℃.

[0118] The corresponding testing standards in Table 1 are: GB / T 1720 (adhesion), GB / T 1731 (flexibility), GB / T 1732 (impact resistance), GB / T 1733 (water resistance), GB / T 1740 (damp heat resistance), GB / T 8625 (flame retardancy), and Appendix B of GB12441-2018 (mass loss, char volume).

[0119] As can be seen from Table 1, the coatings prepared in Examples 1, 4, and 5 of this invention meet the requirements of standard GB 12441-2018 "Fire-retardant Coatings for Finishing" and far exceed the technical specifications of this standard in many aspects. It can also be seen from the table that, compared with Comparative Examples 1-2, Examples 1, 4, and 5 of this invention exhibit better flame-retardant performance.

[0120] 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 green, environmentally friendly, flame-retardant, and waterproof coating, characterized in that: Calculated by weight, including: 80-120 parts waterborne epoxy resin emulsion, 36-58 parts flame retardant filler, 1-3 parts dispersant, 0.2-2 parts defoamer, 0.5-1.5 parts leveling agent, 40-60 parts waterborne curing agent, and 35-55 parts deionized water; The flame-retardant filler is flame-retardant titanium disilicide powder, and the preparation method includes: S1. Weigh 2,5-bis(aminomethyl)furan and ammonium polyphosphate and reflux them in an aqueous solution of ethanol to prepare modified ammonium polyphosphate. S2. Weigh titanium disilicide powder and heat-treat it in an alkaline solution to prepare purified titanium disilicide powder. S3. The purified titanium disilicide powder was reacted with γ-glycidyl etheroxypropyltrimethoxysilane in an aqueous solution by heating to prepare epoxy titanium disilicide powder. S4. Epoxy-based titanium disilicide powder and modified ammonium polyphosphate are mixed in an organic solvent and then heated to react, thus preparing flame-retardant titanium disilicide powder.

2. The green, environmentally friendly, flame-retardant, and waterproof coating according to claim 1, characterized in that, The waterborne epoxy resin emulsion is YPE-20WE0254, with a solid content of 52±2%, an epoxy equivalent of 500-540 g / mol, and a rotor viscosity of 1000-5000 cp / (30℃, 30 rpm); the dispersant is BYK-180; the defoamer is silicone defoamer BYK-024; the leveling agent is BYK-333; and the waterborne curing agent is a water-soluble modified polyamide epoxy curing agent, model AB-HGC-W60.

3. The green and environmentally friendly flame-retardant waterproof coating according to claim 1, characterized in that, The S1 step specifically includes: S1. Weigh out ethanol and deionized water, mix them evenly, and transfer them to a reflux condenser. Inert gas is introduced as a protective gas. 2,5-Di(aminomethyl)furan and ammonium polyphosphate are added in sequence. Under stirring, the temperature is gradually raised to reflux and the reaction is maintained at reflux for 3-6 hours. The solvent is removed by filtration, and the mixture is washed three times with anhydrous ethanol. After drying, modified ammonium polyphosphate is obtained.

4. The green and environmentally friendly flame-retardant waterproof coating according to claim 3, characterized in that, In S1, the mass ratio of 2,5-bis(aminomethyl)furan, ammonium polyphosphate, ethanol and deionized water is 1.26-1.58:2.5-3:30-50:1-5; and the degree of polymerization of ammonium polyphosphate in S1 is 50-100.

5. The green and environmentally friendly flame-retardant waterproof coating according to claim 1, characterized in that, The S2 step specifically includes: S2. Weigh titanium disilicide powder and place it in sodium hydroxide solution. After ultrasonic homogenization, pour it into a flask and stir at 40-50℃ for 1-3 hours. Then, centrifuge to collect the solid product, wash it with distilled water until neutral, and dry it in an oven to obtain purified titanium disilicide powder.

6. The green and environmentally friendly flame-retardant waterproof coating according to claim 5, characterized in that, In S2, the particle size of titanium disilicide powder is 50-100 μm, and the molar concentration of sodium hydroxide solution is 0.05-0.5 mol / L; In S2, the mass ratio of titanium disilicide powder to sodium hydroxide solution is 1:15-25.

7. The green and environmentally friendly flame-retardant waterproof coating according to claim 1, characterized in that, The S3 step specifically includes: S3. The purified titanium disilicide powder was mixed with γ-glycidyl etheroxypropyltrimethoxysilane in deionized water, heated to 50-60℃, stirred for 6-10 h, centrifuged to collect the solid product, washed three times with distilled water, and dried in an oven to obtain epoxy titanium disilicide powder.

8. The green and environmentally friendly flame-retardant waterproof coating according to claim 7, characterized in that, In step S3, the mass ratio of purified titanium disilicide powder, γ-glycidyl etheroxypropyltrimethoxysilane, and deionized water is 1:0.21-0.3:10-20.

9. The green and environmentally friendly flame-retardant waterproof coating according to claim 1, characterized in that, The S4 step specifically includes: S4. Disperse epoxy disilicide powder in N,N-dimethylformamide, homogenize it under ultrasonic action, then add modified ammonium polyphosphate, introduce inert gas as protective gas, stir evenly at room temperature, heat to 60-70℃, stir and react for 2-6 hours, collect the solid product by centrifugation, wash three times with distilled water, and dry to obtain flame retardant disilicide powder. The mass ratio of epoxy-based titanium disilicide powder, modified ammonium polyphosphate, and N,N-dimethylformamide is 1:0.42-0.56:15-25.

10. A method for preparing a green, environmentally friendly, flame-retardant, and waterproof coating according to any one of claims 1-9, characterized in that, include: (1) Weigh out waterborne epoxy resin emulsion, deionized water, flame retardant filler, dispersant, defoamer and leveling agent in sequence and mix them. Each time a component is added, the current component needs to be mixed evenly before adding the next component. After all components are mixed evenly, a mixture is obtained. (2) Weigh out the water-based curing agent and add it to the mixture. After stirring thoroughly, the desired waterproof coating is obtained.