Intumescent fire-retardant anticorrosive coating and its construction method

Abstract

The application provides an intumescent fireproof and anticorrosive coating, which comprises the following components and the mass percentage of each component is as follows: 18-25% of a film forming agent, 22-30% of an acid source, 8-10% of a carbon source, 8-10% of a gas source and 15-25% of an anticorrosive agent, the film forming agent is a mixture of organic silicon modified acrylic resin and water-based epoxy emulsion, the acid source is ammonium polyphosphate or polyphosphate, the carbon source is pentaerythritol or di-pentaerythritol, the gas source is melamine or dicyandiamide, and the anticorrosive agent is a mixture of aluminum tripolyphosphate, zinc phosphate and aluminum silver paste. The application has the functions of fireproofing and anticorrosion at the same time, and the fireproof coating and the anticorrosive coating do not need to be coated respectively, so that the construction process can be reduced, the construction period can be shortened, and the construction cost can be reduced; meanwhile, the effective protection of the base material can reduce the number of maintenance and replacement caused by corrosion or fire damage, and the comprehensive maintenance cost can be reduced in the long run.

Description

Technical Field

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

[0002] Fire-retardant coatings are special coatings applied to the surface of combustible substrates to reduce the flammability of the coated material, inhibit the rapid spread of fire, and improve the fire resistance limit of the coated material.

[0003] The fire-retardant mechanisms of existing fire-retardant coatings can be broadly summarized into the following four points: 1. Fire-retardant coatings are inherently flame-retardant or non-combustible, preventing the protected substrate from direct contact with air, thus delaying ignition and reducing the rate of combustion.

[0004] 2. In addition to being flame-retardant or non-combustible, fire-retardant coatings also have a low thermal conductivity, which can delay the transfer of flame temperature to the protected substrate.

[0005] 3. When heated, fire-retardant coatings decompose into non-flammable inert gases, which dilute the flammable gases released by the protected object, making it less likely to burn or slowing down the burning rate.

[0006] 4. Intumescent fire-retardant coatings expand and foam when heated, forming a carbonaceous foam insulation layer that seals the protected object, delaying the transfer of heat to the substrate and preventing the object from catching fire or experiencing a decrease in strength due to increased temperature.

[0007] Currently, when applying fire-retardant coatings to a substrate, a layer of anti-corrosion coating is typically applied first, followed by the fire-retardant coating. This prevents the fire-retardant coating's effectiveness from being affected by substrate corrosion. However, in practical applications, it has been found that a distinct interface exists between the anti-corrosion coating and the water-based fire-retardant coating, resulting in poor bonding between the two layers. This leads to the fire-retardant coating peeling off, significantly impacting its fire-retardant performance. Even if the fire-retardant and anti-corrosion coatings have a certain bonding strength, when the fire-retardant coating expands under fire, the lack of a firm bond with the substrate causes the formed expanded char layer to easily peel off, severely affecting the fire-retardant effect. Therefore, existing fire-retardant coatings have certain limitations in application. Summary of the Invention

[0008] This invention is made to solve the above-mentioned problems, and its purpose is to provide an intumescent fireproof and anti-corrosion coating and its construction method.

[0009] This invention provides an intumescent fire-retardant and anti-corrosion coating, characterized by comprising the following components in the following mass percentages: 18-27% film-forming agent, 22-32% acid source, 8-12% carbon source, 8-12% gas source, and 15-27% corrosion inhibitor. The film-forming agent is a mixture of silicone-modified acrylic resin and waterborne epoxy emulsion; the acid source is ammonium polyphosphate or polyammonium polyphosphate; the carbon source is pentaerythritol or dipentaerythritol; the gas source is melamine or dicyandiamide; and the preservative is a mixture of aluminum tripolyphosphate, zinc phosphate, and aluminum silver paste.

[0010] This invention also provides a method for applying a fire-retardant and anti-corrosion coating, applicable to any of the above-mentioned intumescent fire-retardant and anti-corrosion coatings, characterized by the following steps: S1. Clean the impurities on the surface of the substrate, and then apply a primer to the surface of the substrate. S2. Mix the film-forming agent, acid source, carbon source, gas source, and corrosion inhibitor to obtain an intumescent fireproof and corrosion-resistant coating. If the coating is too thick during the mixing process, add a thinner during the mixing process. S3. Apply the intumescent fire-retardant and anti-corrosion coating to the surface of the substrate in multiple applications using spraying, brushing, or roller coating methods.

[0011] Furthermore, in step S1, the substrate is treated with sandblasting, shot blasting, or manual grinding to remove rust, and then the oil and dust on the surface of the substrate are cleaned.

[0012] Furthermore, the diluent in step S2 is deionized water.

[0013] Furthermore, in step S3, the thickness of each application of the intumescent fire-retardant and anti-corrosion coating is 0.4~0.6mm, and the interval between each application is at least 4 hours.

[0014] The role and effect of invention The intumescent fire-retardant and anti-corrosion coating of this invention, possessing both fire-retardant and anti-corrosion functions, eliminates the need for separate application of fire-retardant and anti-corrosion coatings, reducing construction steps, shortening the construction period, and lowering construction costs. Simultaneously, its effective protection of the substrate reduces the frequency of repairs and replacements due to corrosion or fire damage, thus lowering overall maintenance costs in the long run. Furthermore, through dual protection of the substrate, it reduces safety hazards caused by substrate corrosion (such as reduced strength due to rust in steel structures) or fire (such as rapid substrate failure) at the source, significantly improving the overall safety level of buildings or equipment and providing more reliable protection for personnel and property. Detailed Implementation

[0015] To make the technical means, creative features, objectives and effects of this invention easy to understand, the following embodiments will specifically illustrate this invention. Example

[0016] This embodiment provides an intumescent fire-retardant and anti-corrosion coating, comprising the following components, with the following mass percentages for each component: 18-27% film-forming agent, 22-32% acid source, 8-12% carbon source, 8-12% gas source, and 15-27% preservative. The film-forming agent is a mixture of silicone-modified acrylic resin and waterborne epoxy emulsion; the acid source is ammonium polyphosphate or polyammonium polyphosphate; the carbon source is pentaerythritol or dipentaerythritol; the gas source is melamine or dicyandiamide; and the preservative is a mixture of aluminum tripolyphosphate, zinc phosphate, and aluminum silver paste.

[0017] In this embodiment, preferably, 25% film-forming agent, 30% acid source, 10% carbon source, 10% gas source, and 25% preservative are selected.

[0018] In this embodiment, the silicone-modified acrylic resin in the film-forming agent imparts excellent weather resistance, chemical corrosion resistance, and flexibility to the fire-retardant and anti-corrosion coating of the present invention, enabling the coating to maintain its integrity under different environments. The water-based epoxy emulsion in the film-forming agent gives the fire-retardant and anti-corrosion coating excellent adhesion and water resistance, ensuring the coating adheres firmly to the substrate surface while meeting environmental protection requirements. For example, in indoor steel structure protection, water-based epoxy emulsion-type intumescent fire-retardant and anti-corrosion coatings can effectively avoid the harm to human health caused by the volatilization of organic solvents.

[0019] In this embodiment, when a fire occurs, the acid source decomposes upon heating to produce strong protic acids such as phosphoric acid, which catalyzes the dehydration of the carbon source into carbon, forming a carbon layer with heat insulation properties. Meanwhile, the gas source decomposes upon heating to release a large amount of non-flammable gases, such as ammonia and carbon dioxide, causing the carbon layer to expand and foam, forming a porous structure, which greatly improves the heat insulation performance, effectively delays the transfer of heat to the substrate, and buys time for personnel evacuation and fire rescue.

[0020] In this embodiment, the aluminum tripolyphosphate and zinc phosphate in the corrosion inhibitor can chemically react with the metal surface to form a dense passivation film, preventing the dissolution of metal ions and the intrusion of corrosive media, thereby achieving a corrosion-resistant effect. The aluminum silver paste, through its physical shielding effect, prevents oxygen, moisture, and other substances from contacting the metal, enhancing the corrosion-resistant effect. For example, in the protection of steel structures in marine engineering, the fire-retardant and corrosion-resistant coating of this invention has a synergistic effect with the corrosion inhibitors, thus effectively resisting seawater erosion.

[0021] After applying the fire-retardant and anti-corrosion coating of this invention, the coating remains stable under normal circumstances, providing protection and decoration. However, when exposed to high-temperature flames, the coating reacts rapidly, the char layer expands and thickens, forming a robust heat-insulating barrier with extremely low thermal conductivity. This effectively prevents heat transfer to the substrate, slowing the rate of temperature increase and maintaining structural strength, thus preventing the steel structure from rapidly deforming and collapsing in a fire. Furthermore, after the fire-retardant and anti-corrosion coating is applied to the substrate, the film-forming agent forms a continuous protective film on the metal surface, isolating it from external corrosive media. The corrosion inhibitor also inhibits the electrochemical corrosion process of the metal through passivation and shielding, reducing the corrosion rate and extending the service life of the metal.

[0022] In summary, the fire-retardant and anti-corrosion coating of this invention can adapt to the needs of complex environments. Specifically, it can meet the conventional fire and corrosion protection requirements of ordinary buildings and industrial plants, as well as the special fire and corrosion protection requirements of marine and petrochemical sites. For example, in marine environments, it can resist the salt spray corrosion of seawater; in petrochemical sites, it can also provide fire protection against hydrocarbon fires, thus demonstrating strong adaptability.

[0023] This embodiment also provides a method for applying a fire-retardant and anti-corrosion coating, applicable to any of the above-mentioned intumescent fire-retardant and anti-corrosion coatings, including the following steps: S1. Clean the impurities on the surface of the substrate, and then apply a primer to the surface of the substrate. S2. Mix the film-forming agent, acid source, carbon source, gas source, and corrosion inhibitor to obtain an intumescent fireproof and corrosion-resistant coating. If the coating is too thick during the mixing process, add a thinner during the mixing process. S3. Apply the intumescent fire-retardant and anti-corrosion coating to the surface of the substrate in multiple applications using spraying, brushing, or roller coating methods.

[0024] The base material is a steel structure.

[0025] In this embodiment, step S1 can be performed by sandblasting, shot blasting, or manual grinding to remove rust from the substrate, followed by cleaning the oil and dust from the substrate surface. The primer can be selected and applied according to the substrate type and the usage environment. For example, epoxy zinc-rich primer, etc.

[0026] In this embodiment, the diluent used in step S2 is preferably deionized water.

[0027] In this embodiment, if a spray gun is used for spraying in step S3, attention should be paid to adjusting the pressure of the spray gun and the nozzle diameter to ensure that the sprayed coating is uniform; if a brush or roller is used, attention should be paid to avoid missed brushing and dripping.

[0028] In this embodiment, the thickness of each application of the intumescent fireproof and anticorrosive coating in step S3 is 0.4~0.6mm, and the interval between each application is at least 4 hours.

[0029] The construction method of the fireproof and anticorrosive coating provided in this embodiment may also include step S4. If it is necessary to further improve the decorativeness and weather resistance of the fireproof and anticorrosive coating, a suitable topcoat may be applied to the fireproof and anticorrosive coating after it has dried.

[0030] The role and effect of the embodiments The intumescent fire-retardant and anti-corrosion coating of this invention, possessing both fire-retardant and anti-corrosion functions, eliminates the need for separate application of fire-retardant and anti-corrosion coatings, reducing construction steps, shortening the construction period, and lowering construction costs. Simultaneously, its effective protection of the substrate reduces the frequency of repairs and replacements due to corrosion or fire damage, thus lowering overall maintenance costs in the long run. Furthermore, through dual protection of the substrate, it reduces safety hazards caused by substrate corrosion (such as reduced strength due to rust in steel structures) or fire (such as rapid substrate failure) at the source, significantly improving the overall safety level of buildings or equipment and providing more reliable protection for personnel and property.

[0031] The above embodiments are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. An intumescent fire-retardant and anti-corrosion coating, characterized in that, It comprises the following components in the following mass percentages: 18-27% film-forming agent, 22-32% acid source, 8-12% carbon source, 8-12% gas source, and 15-27% preservative. The film-forming agent is a mixture of silicone-modified acrylic resin and waterborne epoxy emulsion; the acid source is ammonium polyphosphate or ammonium polyphosphate; the carbon source is pentaerythritol or dipentaerythritol; the gas source is melamine or dicyandiamide; and the preservative is a mixture of aluminum tripolyphosphate, zinc phosphate, and aluminum silver paste.

2. A method for applying a fire-retardant and anti-corrosion coating, applicable to the intumescent fire-retardant and anti-corrosion coating as described in claim 1, characterized in that, Includes the following steps: S1. Clean the impurities on the surface of the substrate, and then apply a primer to the surface of the substrate; S2. The film-forming agent, the acid source, the carbon source, the gas source, and the corrosion inhibitor are mixed to obtain the intumescent fireproof and corrosion-resistant coating. If the coating is too thick during the mixing process, a diluent is added during the mixing process. S3. Apply the intumescent fire-retardant and anti-corrosion coating to the surface of the substrate in multiple applications using spraying, brushing, or roller coating methods.

3. The construction method according to claim 2, characterized in that: In step S1, the substrate is treated to remove rust by sandblasting, shot blasting, or manual grinding, and then the oil and dust on the surface of the substrate are cleaned.

4. The construction method according to claim 2, characterized in that: In step S2, the diluent is deionized water.

5. The construction method according to claim 2, characterized in that: In step S3, the thickness of each application of the intumescent fireproof and anticorrosive coating is 0.4 to 0.6 mm, and the interval between each application is at least 4 hours.