Nano-modified inorganic transparent fireproof coating and preparation method thereof

Abstract

The invention discloses a nano-modified inorganic transparent fireproof coating and a preparation method thereof. The nano-modified inorganic transparent fireproof coating comprises the following components in parts by mass: 40-60 parts of a modified potassium silicate solution, 2 parts of a silane coupling agent, 1 part of hydroxyethyl cellulose, 0.3 part of polyether modified siloxane and 15 parts of deionized water. The modified potassium silicate solution is prepared from the following components in parts by mass: 50 to 70 parts of potassium silicate solution with the concentration of 30 to 40 percent and the modulus of 3.0 to 3.5, 5 to 10 parts of nano silicon dioxide and 2 to 5 parts of nano aluminum oxide; 1-3 parts of a stabilizer, 15-25 parts of deionized water and a proper amount of a pH regulator. The nano-modified inorganic transparent fireproof coating is mainly prepared from inorganic components, the preparation method is simple, the nano-modified inorganic transparent fireproof coating has relatively high light transmittance and fire resistance and relatively good weather resistance and environmental friendliness, and the performance and quality of a product are improved.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a nano-modified inorganic transparent fire-retardant coating and its preparation method. Background Technology

[0002] Transparent fire-retardant coatings combine transparency and fire resistance, effectively increasing the ignition point of objects and significantly slowing the spread of fire, thus buying time for evacuation and firefighting. For example, applying a transparent fire-retardant coating to the surface of wooden furniture can greatly reduce its burning rate when exposed to an open flame. Due to its high transparency, the coating maintains the original texture, color, and appearance of the substrate, offering strong decorative appeal. When used on wooden components of ancient buildings or high-end furniture, it provides fire protection without compromising its original exquisite appearance.

[0003] Current transparent fire-retardant coatings use large amounts of organic materials, such as acrylic resin, polyurethane resin, and epoxy resin, resulting in poor environmental performance. Furthermore, the addition of flame retardants affects their transparency. Existing transparent fire-retardant coatings have the following drawbacks:

[0004] First, balancing transparency and fire resistance is challenging. To maintain high transparency, the amount of flame retardant added to the coating is limited, which may result in fire resistance performance that is inferior to thicker or opaque fire-retardant coatings. Although intumescent transparent fire-retardant coatings can form an insulating char layer, this layer may not be dense enough at extreme temperatures, resulting in limited fire resistance time.

[0005] Secondly, the coating film is relatively brittle. Some transparent fire-retardant coatings (such as those based on acrylic resin or amino resin) are brittle, lack impact resistance and flexibility, and are prone to cracking or peeling under stress or vibration.

[0006] Secondly, insufficient weather resistance, especially for water-based coatings, makes them susceptible to damage from ultraviolet rays, moisture, and temperature differences when exposed to outdoor environments for extended periods, leading to whitening, cracking, or peeling of the coating.

[0007] Finally, some transparent fire-retardant coatings have poor heat resistance and may creep at high temperatures, leading to a decrease in coating adhesion strength. For example, transparent fire-retardant coatings based on acrylic resins have a low softening point (50-90℃), and the coating is prone to softening or failure under high-temperature environments.

[0008] To solve the above problems, there is an urgent need to develop a new type of transparent fire-retardant coating.

[0009] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0010] This invention provides a nano-modified inorganic transparent fire-retardant coating, aiming to solve the current problems of transparent fire-retardant coatings, such as difficulty in balancing transparency and fire resistance, high film brittleness, insufficient weather resistance, and poor heat resistance.

[0011] To achieve the above objectives, the present invention provides the following technical solution:

[0012] A nano-modified inorganic transparent fire-retardant coating, comprising the following components by mass:

[0013] 40-60 parts modified potassium silicate solution, 2 parts silane coupling agent, 1 part hydroxyethyl cellulose, 0.3 parts polyether modified siloxane, and 15 parts deionized water;

[0014] The modified potassium silicate solution comprises the following components by mass:

[0015] 50-70 parts of potassium silicate solution with a concentration of 30%-40% and a modulus of 3.0-3.5, 5-10 parts of nano-silica, 2-5 parts of nano-alumina; 1-3 parts of stabilizer, 15-25 parts of deionized water, and an appropriate amount of pH adjuster.

[0016] Furthermore, the stabilizer is polyethylene glycol (PEG-400).

[0017] Furthermore, the pH adjuster is 10% phosphoric acid, which adjusts the pH value of the modified potassium silicate solution to 8-9.

[0018] Furthermore, the particle size of nano-silica is 10-20 nm, and the particle size of nano-alumina is 20-30 nm.

[0019] This invention also provides a method for preparing a nano-modified inorganic transparent fire-retardant coating, comprising the following steps:

[0020] S1, Preparation of modified potassium silicate solution:

[0021] Step 1: Pretreatment of potassium silicate solution

[0022] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 30%-40%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0023] pH adjustment: Use a pH adjuster to adjust the pH of the potassium silicate solution to 8-9.

[0024] Step 2: Blending and Reaction

[0025] Add 5-10 parts of nano-silica, 2-5 parts of nano-alumina, 1-3 parts of stabilizer, and 15-25 parts of deionized water to a potassium silicate solution with a concentration of 30%-40%, a modulus of 3.0-3.5, and a mass fraction of 50-70 parts. Stir at 200-500 rpm, heat to 50-80℃, and stir at a constant temperature for 1-3 hours.

[0026] After the reaction is complete, the pH of the potassium silicate solution is adjusted to 8-9 using a pH adjuster.

[0027] S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 40-60 parts of modified potassium silicate solution prepared in S1. Stir with a stirrer at 400 rpm and control the temperature at 50-60℃ for 1-3 hours.

[0028] Furthermore, the stabilizer is polyethylene glycol (PEG-400).

[0029] Furthermore, the pH adjuster is 10% phosphoric acid.

[0030] Furthermore, the particle size of nano-silica is 10-20 nm, and the particle size of nano-alumina is 20-30 nm.

[0031] Furthermore, the stirring temperature in S1 is preferably 65°C, and the stirring temperature in S2 is preferably 55°C.

[0032] Furthermore, the stirring speed in S1 is preferably 350 rpm, and the stirring time in S1 and S2 is preferably 2 hours.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] Transparent protection: Light transmittance ≥80%, color difference ΔE <1.5, perfectly preserving the wood grain and authenticity.

[0035] Highly effective fire protection: fire resistance limit of 30 minutes (900℃), heat release rate reduced by 92%, suppressing the risk of flashover.

[0036] Multi-functional synergy: Integrates fireproof, corrosion-proof, and moisture-proof functions, extending the maintenance cycle to 5 years.

[0037] High durability: Excellent UV resistance and weather resistance; the coating is not prone to yellowing or peeling, maintaining its aesthetic appeal and protective effect for a long time.

[0038] Green and environmentally friendly: Water-based substrate, VOC emissions ≤50g / L, in line with the standards of the "Green Building Materials Promotion Catalog". Attached Figure Description

[0039] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this disclosure and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart of the preparation process for nano-modified inorganic transparent fireproof coatings. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The number of embodiments in the accompanying drawings is only for illustrative purposes and is not intended to limit the present invention. Based on the embodiments of the invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. Where specific conditions are not specified in this embodiment, conventional conditions or conditions recommended by the manufacturer shall be followed. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0042] Example 1:

[0043] A method for preparing a nano-modified inorganic transparent fire-retardant coating, the method comprising the following steps:

[0044] S1, Preparation of modified potassium silicate solution:

[0045] Step 1: Pretreatment of potassium silicate solution

[0046] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 30%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0047] pH adjustment: Adjust the pH of the potassium silicate solution to 8 using 10% phosphoric acid.

[0048] Step 2: Blending and Reaction

[0049] Add 5 parts of nano-silica, 2 parts of nano-alumina, 1 part of polyethylene glycol (PEG400), and 15 parts of deionized water to a potassium silicate solution with a concentration of 30%, a modulus of 3.0, and a mass fraction of 50 parts. Stir at 200 rpm, heat to 50°C, and stir at a constant temperature for 1 hour.

[0050] After the reaction is complete, the pH of the potassium silicate solution is adjusted to 8 using a pH adjuster.

[0051] S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 40 parts of modified potassium silicate solution prepared in S1. Stir with a stirrer at a speed of 400 rpm and a temperature of 50°C for 1 hour.

[0052] Example 2:

[0053] Preparation of a sodium SiO2-modified potassium silicate solution:

[0054] Step 1: Pretreatment of potassium silicate solution

[0055] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 35%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0056] pH adjustment: Adjust the pH of the potassium silicate solution to 8.5 using a pH adjuster.

[0057] Step 2: Blending and Reaction

[0058] Add 7.5 parts of nano-silica, 3.5 parts of nano-alumina, 2 parts of polyethylene glycol (PEG400), and 20 parts of deionized water to a potassium silicate solution with a concentration of 35%, a modulus of 3.25, and a mass fraction of 60 parts. Stir at 350 rpm, heat to 65°C, and stir at a constant temperature for 2 hours.

[0059] After the reaction was complete, the pH of the potassium silicate solution was adjusted to 8.5 using 10% phosphoric acid.

[0060] S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 50 parts of modified potassium silicate solution prepared in S1. Stir with a stirrer at a speed of 400 rpm and a temperature of 55℃ for 2 hours.

[0061] Example 3:

[0062] A method for preparing a nano-modified inorganic transparent fire-retardant coating, the method comprising the following steps:

[0063] S1, Preparation of modified potassium silicate solution:

[0064] Step 1: Pretreatment of potassium silicate solution

[0065] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 40%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0066] pH adjustment: Adjust the pH of the potassium silicate solution to 9 using 10% phosphoric acid.

[0067] Step 2: Blending and Reaction

[0068] Add 10 parts of nano-silica, 5 parts of nano-alumina, 3 parts of polyethylene glycol (PEG400), and 25 parts of deionized water to a potassium silicate solution with a concentration of 40%, a modulus of 3.5, and a mass fraction of 70 parts. Stir at 500 rpm, heat to 80°C, and maintain the temperature for 3 hours.

[0069] After the reaction was complete, the pH of the potassium silicate solution was adjusted to 9 using 10% phosphoric acid.

[0070] S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 40-60 parts of modified potassium silicate solution prepared in S1. Stir with a stirrer at 400 rpm and control the temperature at 60℃ for 3 hours.

[0071] Example 4:

[0072] A method for preparing a nano-modified inorganic transparent fire-retardant coating, the method comprising the following steps:

[0073] S1, Preparation of modified potassium silicate solution:

[0074] Step 1: Pretreatment of potassium silicate solution

[0075] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 38%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0076] pH adjustment: Adjust the pH of the potassium silicate solution to 8.8 using a pH adjuster.

[0077] Step 2: Blending and Reaction

[0078] Add 8.5 parts of nano-silica, 4 parts of nano-alumina, 2.5 parts of polyethylene glycol (PEG400), and 23 parts of deionized water to a potassium silicate solution with a concentration of 38%, a modulus of 3.4, and a mass fraction of 65 parts. Stir at 400 rpm, heat to 74°C, and maintain the temperature for 2.5 hours.

[0079] After the reaction was complete, the pH of the potassium silicate solution was adjusted to 8.8 using a pH adjuster.

[0080] S2, Preparation of transparent fireproof coating: 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane were added to 58 parts of modified potassium silicate solution prepared in S1. The mixture was stirred in a stirrer at a speed of 400 rpm and the temperature was controlled at 58℃ for 2.5 hours.

[0081] Example 5:

[0082] A method for preparing a nano-modified inorganic transparent fire-retardant coating, the method comprising the following steps:

[0083] S1, Preparation of modified potassium silicate solution:

[0084] Step 1: Pretreatment of potassium silicate solution

[0085] Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 32%, and filter it through a 0.45μm filter membrane to remove insoluble impurities.

[0086] pH adjustment: Adjust the pH of the potassium silicate solution to 8.2 using a pH adjuster.

[0087] Step 2: Blending and Reaction

[0088] Add 6 parts of nano-silica, 2.5 parts of nano-alumina, 1.4 parts of polyethylene glycol (PEG400), and 17 parts of deionized water to a potassium silicate solution with a concentration of 32%, a modulus of 3.1, and a mass fraction of 54 parts. Stir at 300 rpm, heat to 56°C, and maintain the temperature for 1.5 hours.

[0089] After the reaction was complete, the pH of the potassium silicate solution was adjusted to 8.2 using a pH adjuster.

[0090] S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 45 parts of modified potassium silicate solution prepared in S1. Stir with a mixer at a speed of 400 rpm and a temperature controlled at 52-60℃ for 1.5 hours.

[0091] The principle of this invention is:

[0092] High-temperature ceramization: Water-soluble inorganic intumescent flame retardants undergo chemical changes at high temperatures (such as in fire environments), reacting with the substrate or other additives (such as alumina, aluminates, etc.) to form a hard ceramized layer. This layer has a dense structure, excellent thermal insulation and fire resistance, and can effectively block heat transfer, protecting the substrate from high-temperature damage.

[0093] Endothermic decomposition: Water-soluble inorganic intumescent flame retardants may release water of crystallization or undergo decomposition reactions when heated, absorbing a large amount of heat, reducing the temperature of the surrounding environment, thereby delaying the thermal degradation and combustion process of the substrate.

[0094] Oxygen barrier: The ceramicized layer has low permeability, which can effectively prevent oxygen from entering the combustion zone, inhibit the spread of flame and the continuation of combustion reaction.

[0095] Structural stability: The protective layer formed by the water-soluble inorganic intumescent flame retardant remains structurally stable at high temperatures and is not easily disintegrated. It can maintain its fireproof and heat-insulating effects for a long time and is particularly suitable for fireproofing of cables, coatings and building materials.

[0096] The specific functions of each component are:

[0097] 1. Potassium silicate solution: the main film-forming substance

[0098] 2. Polyethylene glycol (PEG400): Provides film-forming assistance.

[0099] 3. Nano-silica: Provides a framework layer

[0100] 4. Nano-alumina: Flame retardant

[0101] 5. Silane coupling agents: hydrolysis-assisted film formation

[0102] 6. Hydroxyethyl cellulose: Viscosity adjuster

[0103] 7. Polyether-modified siloxane: Hydrolysis-assisted film formation

[0104] Verification of the technical effects of this invention:

[0105] Product performance parameters obtained in each embodiment

[0106]

[0107] Therefore, it can be seen that the nano-modified inorganic transparent fireproof coating and its preparation method provided by the present invention have significant technical effects.

[0108] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A nano-modified inorganic transparent fire-retardant coating, characterized in that, Includes the following mass components: 40-60 parts modified potassium silicate solution, 2 parts silane coupling agent, 1 part hydroxyethyl cellulose, 0.3 parts polyether modified siloxane, and 15 parts deionized water; The modified potassium silicate solution comprises the following components by mass: 50-70 parts of potassium silicate solution with a concentration of 30%-40% and a modulus of 3.0-3.5, 5-10 parts of nano-silica, 2-5 parts of nano-alumina; 1-3 parts of stabilizer, 15-25 parts of deionized water, and an appropriate amount of pH adjuster.

2. The nano-modified inorganic transparent fire-retardant coating according to claim 1, characterized in that, The stabilizer is polyethylene glycol (PEG-400).

3. The nano-modified inorganic transparent fire-retardant coating according to claim 1, characterized in that, The pH adjuster is 10% phosphoric acid, which adjusts the pH of the modified potassium silicate solution to 8-9.

4. The nano-modified inorganic transparent fire-retardant coating according to claim 1, characterized in that, The nano-silica has a particle size of 10-20 nm, and the nano-alumina has a particle size of 20-30 nm.

5. A method for preparing a nano-modified inorganic transparent fire-retardant coating, characterized in that, Includes the following steps: S1, Preparation of modified potassium silicate solution: Step 1: Pretreatment of potassium silicate solution Dilution and filtration: Dilute the high-concentration potassium silicate solution with deionized water to the target concentration of 30%-40%, and filter it through a 0.45μm filter membrane to remove insoluble impurities. pH adjustment: Adjust the pH of the potassium silicate solution to 8-9 using 10% phosphoric acid. Step 2: Blending and Reaction Add 5-10 parts of nano-silica, 2-5 parts of nano-alumina, 1-3 parts of stabilizer, and 15-25 parts of deionized water to a potassium silicate solution with a concentration of 30%-40%, a modulus of 3.0-3.5, and a mass fraction of 50-70 parts. Stir at 200-500 rpm, heat to 50-80℃, and stir at a constant temperature for 1-3 hours. After the reaction is complete, adjust the pH of the potassium silicate solution to 8-9 with 10% phosphoric acid. S2, Preparation of transparent fireproof coating: Add 15 parts of deionized water, 2 parts of silane coupling agent, 1 part of hydroxyethyl cellulose, and 0.3 parts of polyether modified siloxane to 40-60 parts of modified potassium silicate solution prepared in S1. Stir with a stirrer at 400 rpm and control the temperature at 50-60℃ for 1-3 hours.

6. The method for preparing a nano-modified inorganic transparent fire-retardant coating according to claim 5, characterized in that, The stabilizer is polyethylene glycol, PEG-400.

7. The method for preparing a nano-modified inorganic transparent fire-retardant coating according to claim 5, characterized in that, The pH adjuster is 10% phosphoric acid, which adjusts the pH of the modified potassium silicate solution to 8-9.

8. The method for preparing a nano-modified inorganic transparent fire-retardant coating according to claim 5, characterized in that, The nano-silica has a particle size of 10-20 nm, and the nano-alumina has a particle size of 20-30 nm.

9. The method for preparing a nano-modified inorganic transparent fire-retardant coating according to claim 5, characterized in that, The preferred stirring temperature in S1 is 65℃, and the preferred stirring temperature in S2 is 55℃.

10. The method for preparing a nano-modified inorganic transparent fire-retardant coating according to claim 5, characterized in that, The preferred stirring speed in S1 is 350 rpm, and the preferred stirring time in S1 and S2 is 2 hours.

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