Transparent intumescent fireproof coating as well as preparation method and application thereof

Abstract

The invention relates to the technical field of coatings, in particular to a transparent intumescent fireproof coating as well as a preparation method and application thereof. The coating comprises the following components: 40-50% of water-based acrylate resin, 3-7% of an acid source, 5-10% of a carbon source, 5-10% of a gas source, 3-7% of a filler, 1-5% of a coalescing agent, 0.5-3% of a dispersant, 0.1-1% of a leveling agent, 0.1-0.8% of a defoaming agent, 0.5-3% of an ultraviolet light absorber and the balance of deionized water. By limiting the weight ratio of the acid source to the carbon source to the gas source to the filler to be 5: (5-10): (5-10): (4-7), the fireproof, transparent and adhesive properties can be balanced; the water-based acrylate resin comprises an anionic methacrylic acid emulsion, and the viscosity of the emulsion at 25 DEG C is 5-50 mPa.s, so that the stability of the coating can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a transparent intumescent fire retardant coating and a preparation method and application thereof. Background Art

[0002] Transparent intumescent fire retardant coatings are formulated using water as a solvent, an organic-inorganic composite binder, and additives such as high-efficiency flame retardants, foaming agents, and additives. They are environmentally friendly, non-toxic, and pollution-free. After drying, the coating forms a smooth, transparent film, offering both decorative and aesthetic appeal. Their superior transparency complements the natural wood grain, transcending the limitations of traditional fire retardant coatings, which often obscure decorative effects. However, transparent intumescent fire retardant coatings currently face challenges in maintaining a balance between transparency, fire rating, adhesion, and stability.

[0003] Chinese invention patent application CN103073935A discloses a transparent intumescent fire-retardant coating and its preparation method. The coating comprises the following components, by mass percentage: 40-60% acid source resin, 20-50% gas source methyl etherified amino resin, 3-10% carbon source pentaerythritol triacrylate, 2-6% initiator, 0.5-2% leveling agent, and 0.5-2% defoaming agent silicone resin, with the sum of these components being 100%. The coating is stirred evenly at 40-60°C and cured by ultraviolet light or low-energy electron beam irradiation to obtain the transparent intumescent fire-retardant coating. This transparent fire-retardant coating has a simple preparation method, a significant expansion effect, a high oxygen index, and excellent fire-retardant properties, but its adhesion and stability have not been investigated. Summary of the Invention

[0004] The first aspect of the present invention provides a transparent intumescent fire retardant coating, which comprises, by weight percentage, 40-50% of a water-based acrylic resin, 3-7% of an acid source, 5-10% of a carbon source, 5-10% of a gas source, 3-7% of a filler, 1-5% of a film-forming aid, 0.5-3% of a dispersant, 0.1-1% of a leveling agent, 0.1-0.8% of a defoaming agent, 0.5-3% of an ultraviolet absorber, and the balance made up of deionized water.

[0005] Optionally, the components include, by weight percentage: 42-48% water-based acrylic resin, 4-6% acid source, 6-10% carbon source, 5-8% gas source, 4-7% filler, 1-4% film-forming aid, 0.5-2% dispersant, 0.1-1% leveling agent, 0.1-0.8% defoaming agent, 0.5-1.5% ultraviolet absorber, and deionized water to make up the balance.

[0006] The acid source includes coated ammonium polyphosphate.

[0007] The gas source includes at least one of melamine, dicyandiamide, and amino resin decomposition products.

[0008] Optionally, the gas source includes melamine, and the melamine is micronized, and the particle size of the melamine after treatment is not greater than 300 nm.

[0009] The carbon source includes at least one of pentaerythritol triacrylate, pentaerythritol, dipentaerythritol, and starch.

[0010] The weight ratio of the acid source, carbon source, gas source and filler is 5: (5-10): (5-10): (4-7).

[0011] Optionally, the weight ratio of the acid source, carbon source, gas source and filler is 5: (6-10): (5-8): (4-7).

[0012] Researchers have discovered that by limiting the weight ratio of the acid source, carbon source, gas source, and filler to 5:(5-10):(5-10):(4-7), a balanced fireproofing, transparency, and adhesion properties can be achieved. This precise ratio of the acid source, carbon source, gas source, and filler achieves a synergistic effect of catalytic carbonization, gas expansion, and structural reinforcement. This promotes filler dispersion in the resin, avoiding differences in light refraction caused by large particles, thereby improving transparency. The flexible segments in the acid source polymer enhance the adhesion of the coating to the substrate, increasing the coating's cohesion and bonding strength to the substrate.

[0013] The water-based acrylic resin includes an anionic methacrylic acid emulsion, and the viscosity of the emulsion at 25° C. is 5-50 mPa·s.

[0014] Optionally, the viscosity of the emulsion at 25° C. is 5-50 mPa·s.

[0015] The filler includes at least one of zinc borate, magnesium hydroxide, and magnesium aluminum silicate.

[0016] Optionally, the filler comprises zinc borate.

[0017] The filler further comprises at least one of nano-montmorillonite and fumed silica.

[0018] Optionally, the filler includes nano-montmorillonite and fumed silica, and the mass ratio of the nano-montmorillonite to the fumed silica is 1:(0.05-0.5).

[0019] Optionally, the mass ratio of the nano-montmorillonite to the fumed silica is 1:(0.05-0.2).

[0020] Optionally, the specific surface area (BET method) of the fumed silica is 200-400 m2 / g.

[0021] The film-forming aid includes alcohol ester compounds.

[0022] The film-forming aid includes but is not limited to at least one of the following brands: ester-12, ester-16, and Eastman TEXANOL.

[0023] The dispersant includes but is not limited to at least one of the following brands: BYK-190, Disuper S19, DS-195H, DH-6190S, and YMY-790W.

[0024] The leveling agent includes but is not limited to at least one of the following brands: TEGO Glide 410, TEGO Glide 450, TEGO Glide 435, TEGO Glide B1484, and BVK-410.

[0025] The ultraviolet absorber includes but is not limited to at least one of the following brands: Tinuvin 1130, Tinuvin 329, Tinuvin 384-2, Hostavin 3050, and Cyasorb UV-1164.

[0026] Optionally, the conductivity of the deionized water is ≤5 μS / cm.

[0027] A second aspect of the present invention provides a method for preparing a transparent intumescent fire retardant coating, comprising the following steps: S1, after deionized water, dispersant and defoamer are mixed uniformly to obtain a mixed solution, an acid source, a carbon source, a gas source and a filler are added to the mixed solution and mixed uniformly to obtain a pre-dispersion solution; S2, mixing a water-based acrylic resin with a film-forming aid and a leveling agent to obtain a resin mixed solution; S3, adding the resin mixed solution to the pre-dispersion solution, adding the ultraviolet absorber, and stirring evenly.

[0028] Optionally, the fineness of the pre-dispersion liquid is not greater than 50 μm.

[0029] A third aspect of the present invention provides an application of a transparent intumescent fire retardant coating, which is applied to coating the surface of wooden products, bamboo products or fiber products.

[0030] The dry film thickness of the coating is 300-600 μm.

[0031] Optionally, the dry film thickness of the coating is 350-500 μm.

[0032] Beneficial effects: 1. By limiting the weight ratio of acid source, carbon source, gas source and filler to 5: (5-10): (5-10): (4-7), the fireproofing, transparency and adhesion properties can be balanced.

[0033] 2. The water-based acrylic resin includes an anionic methacrylic acid emulsion, and the viscosity of the emulsion at 25° C. is 5-50 mPa·s, which can improve the stability of the coating.

[0034] 3. The filler includes nano-montmorillonite and fumed silica, and the mass ratio of nano-montmorillonite to fumed silica is limited to 1: (0.05-0.5), which can simultaneously improve the stability and expansion ratio of the fire retardant coating.

[0035] 4. The coating prepared in this application can meet the thin coating process (dry film thickness 300-600μm) and achieve excellent burning resistance.

[0036] 5. The coating prepared in this application has a simple process and can be applied to the surfaces of wood products, bamboo products or fiber products. DETAILED DESCRIPTION

[0037] Example 1 A transparent intumescent fire retardant coating comprises, by weight percentage, 45% of a water-based acrylic resin (anionic methacrylic acid emulsion with a viscosity of 15 mPa·s at 25° C., DSM NeoCryl XK-52), 5% of an acid source (encapsulated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 8% of a carbon source (pentaerythritol), 7% of a gas source (melamine), 5% of a filler (zinc borate), 3% of a film-forming aid (alcohol ester-12), 1.5% of a dispersant (BYK-190), 0.5% of a leveling agent (TEGO Glide 410), 0.3% of a defoamer (BYK-028), 1% of a UV absorber (Tinuvin 1130), and the balance made up of deionized water.

[0038] The melamine is micronized, and the particle size of the melamine after the treatment is 300 nm.

[0039] A preparation method of a transparent intumescent fire retardant coating comprises the following steps: adding deionized water, a dispersant and a defoamer into a reactor, stirring at 300 rpm for 5 minutes, adding an acid source, a carbon source, a gas source and a filler into the reactor, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm, thereby obtaining a pre-dispersion liquid; mixing a water-based acrylic resin with a film-forming aid and a leveling agent, stirring at 600 rpm for 10 minutes, thereby obtaining a resin mixed solution; adding the resin mixed solution into the pre-dispersion liquid, stirring at 800 rpm for 20 minutes, adding an ultraviolet absorber, continuing stirring for 10 minutes, filtering through a 400-mesh sieve, and standing for defoaming for 24 hours.

[0040] A transparent intumescent fire retardant coating is used for coating the surface of wooden products by wet spraying with a dry film thickness of 400 μm.

[0041] Example 2 The specific implementation is the same as that of Example 1; the difference is that the filler in Example 2 is zinc borate, nano-montmorillonite and fumed silica, and the weight ratio of zinc borate, nano-montmorillonite and fumed silica is 4.78:0.02:0.2.

[0042] Example 3 The specific implementation method is the same as that of Example 1; except that, in Example 3, the components are: 48% of an aqueous acrylic resin (anionic methacrylic acid emulsion, viscosity of 15 mPa·s at 25° C., DSM NeoCryl XK-52), 4% of an acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 7% of a carbon source (pentaerythritol), 6% of a gas source (melamine), 5% of a filler (zinc borate + nano-montmorillonite + fumed silica, mass ratio of 4.5:0.3:0.2), 2.5% of a film-forming aid (Eastman TEXANOL), 2% of a dispersant (BYK-190), 0.4% of a leveling agent (TEGO Glide 435), 0.3% of a defoamer (BYK-028), 1.5% of a UV absorber (Tinuvin 329), and the balance made up of deionized water.

[0043] Comparative Example 1 A fire-retardant coating, comprising, by weight percentage, 50% epoxy resin (Huaguoshan 101 emulsion + GZ26 curing agent), 25% acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 5% carbon source (starch), 15% filler (magnesium hydroxide), and the balance made up of deionized water.

[0044] A method for preparing a fire retardant coating comprises the following steps: adding an acid source, a carbon source and a filler to deionized water, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm to obtain a pre-dispersion liquid; adding epoxy resin to the pre-dispersion liquid, maintaining stirring at 800 rpm for 20 minutes, filtering through a 400-mesh sieve, and standing for 24 hours.

[0045] The invention discloses an application of a fire retardant coating, which is applied to the surface of wooden products by wet spraying, with a dry film thickness of 400 μm.

[0046] Comparative Example 2 A fire retardant coating comprises, by weight percentage, 50% epoxy resin (Huaguoshan 101 emulsion + GZ26 curing agent), 15% acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 15% filler (magnesium aluminum silicate), 2% film-forming aid (alcohol ester-12), 1% dispersant (BYK-190), 0.3% leveling agent (TEGO Glide 410), 0.2% defoaming agent (BYK-028), 5% ultraviolet absorber (Tinuvin 1130), and the balance made up of deionized water.

[0047] A method for preparing a fire retardant coating comprises the following steps: adding deionized water, a dispersant and a defoamer into a reactor, stirring at 300 rpm for 5 minutes, adding an acid source and a filler into the reactor, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm, thereby obtaining a pre-dispersion liquid; mixing a two-component epoxy resin with a film-forming aid and a leveling agent, stirring at 600 rpm for 10 minutes, thereby obtaining a resin mixed solution; adding the resin mixed solution into the pre-dispersion liquid, stirring at 800 rpm for 20 minutes, adding an ultraviolet absorber, continuing stirring for 10 minutes, filtering through a 400-mesh sieve, and standing for defoaming for 24 hours.

[0048] The invention discloses an application of a fire retardant coating, which is applied to the surface of wooden products by wet spraying, with a dry film thickness of 400 μm.

[0049] Comparative Example 3 A fire-retardant coating comprises, by weight percentage, 50% epoxy resin (Huaguoshan 101 emulsion + GZ26 curing agent), 10% acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 5% carbon source (pentaerythritol), 10% filler (zinc borate), and the balance made up of deionized water.

[0050] A method for preparing a fire retardant coating comprises the following steps: adding an acid source, a carbon source and a filler to deionized water, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm to obtain a pre-dispersion liquid; adding epoxy resin to the pre-dispersion liquid, maintaining stirring at 800 rpm for 20 minutes, filtering through a 400-mesh sieve, and standing for 24 hours.

[0051] The invention discloses an application of a fire retardant coating, which is applied to the surface of wooden products by wet spraying, with a dry film thickness of 400 μm.

[0052] Comparative Example 4 A fire-retardant coating, comprising, by weight percentage, 50% epoxy resin (Huaguoshan 101 emulsion + GZ26 curing agent), 5% acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 5% gas source (urea), 15% filler (aluminum hydroxide), 2% film-forming aid (propylene glycol), 1% dispersant (BYK-190), and the balance made up of deionized water.

[0053] A method for preparing a fire retardant coating comprises the following steps: adding an acid source, a gas source and a filler to deionized water mixed with a dispersant, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm to obtain a pre-dispersion liquid; uniformly mixing an epoxy resin and a film-forming aid, adding the mixture to the pre-dispersion liquid, maintaining stirring at 800 rpm for 20 minutes, filtering through a 400-mesh sieve, and standing for 24 hours.

[0054] The invention discloses an application of a fire retardant coating, which is applied to the surface of wooden products by wet spraying, with a dry film thickness of 400 μm.

[0055] Comparative Example 5 A fire-retardant coating comprises, by weight percentage, 50% epoxy resin (Huaguoshan 101 emulsion + GZ26 curing agent), 20% acid source (coated ammonium polyphosphate, type II, brand: Clariant Exolit AP422), 5% carbon source (pentaerythritol), 5% gas source (melamine), 15% filler (magnesium silicate), and the balance made up of deionized water.

[0056] A method for preparing a fire retardant coating comprises the following steps: adding an acid source, a carbon source, a gas source, and a filler to deionized water, increasing the rotation speed to 1200 rpm and dispersing for 30 minutes until the fineness reaches 50 μm, to obtain a pre-dispersion liquid; adding epoxy resin to the pre-dispersion liquid, maintaining stirring at 800 rpm for 20 minutes, filtering through a 400-mesh sieve, and standing for defoaming for 24 hours.

[0057] The invention discloses an application of a fire retardant coating, which is applied to the surface of wooden products by wet spraying, with a dry film thickness of 400 μm.

[0058] Comparative Example 6 The specific implementation is the same as Example 1; the difference is that the weight ratio of the acid source, carbon source, gas source and filler in Comparative Example 6 is 5:4:4:3.

[0059] Performance testing methods The fire retardant coatings prepared in the Examples and Comparative Examples were coated with films to a dry film thickness of 0.5 mm. The coatings were sprayed at a pressure of 0.3-0.5 MPa and cured at 25°C for 48 hours. The coatings were then tested for fire rating, transparency, adhesion, weather resistance, expansion ratio, and stability. The film thickness for the burn-time test was based on the dry film thickness of the Examples and Comparative Examples. The test data are listed in Table 1.

[0060] Fire protection level: Refer to GB 12441-2018 standard.

[0061] Transparency: Refer to ASTM D1003 standard, where transparency greater than 82% is considered "high", between 75% and 82% (inclusive) is considered "medium", and below 75% is considered "low".

[0062] Adhesion: Refer to GB / T 1720 standard.

[0063] Weathering resistance: ΔE (color difference) after 500h of QUV aging.

[0064] Expansion ratio: Passed high temperature furnace test (800℃×10min).

[0065] Burning time: Refer to GB 12441-2018 standard test.

[0066] Stability: Store at room temperature for 6 months and observe the properties.

[0067] Performance test data Table 1

[0068] As shown in Table 1, the fire retardant coating prepared by the present invention has excellent fire retardancy, transparency, adhesion, weather resistance ΔE, expansion ratio, burning time and stability; compared with the preferred embodiment, the comprehensive performance of Comparative Examples 1-5 is significantly reduced because the acid source, carbon source and gas source are not used simultaneously; Comparative Example 6 has a loose expanded carbon layer due to the compounding of the acid source, carbon source, gas source and filler outside the preferred range, the burning time is only 15 minutes, and the adhesion is reduced to 2B.

Claims

1. A transparent intumescent fire retardant coating, characterized in that: Calculated by weight percentage, the components include: 40-50% water-based acrylic resin, 3-7% acid source, 5-10% carbon source, 5-10% gas source, 3-7% filler, 1-5% film-forming aid, 0.5-3% dispersant, 0.1-1% leveling agent, 0.1-0.8% defoamer, 0.5-3% ultraviolet absorber, and deionized water to make up the balance. The weight ratio of the acid source, carbon source, gas source and filler is 5: (5-10): (5-10): (4-7).

2. The transparent intumescent fire retardant coating according to claim 1, characterized in that: The acid source includes coated ammonium polyphosphate.

3. The transparent intumescent fire retardant coating according to claim 1, characterized in that: The weight ratio of the acid source, carbon source, gas source and filler is 5: (6-10): (5-8): (4-7).

4. The transparent intumescent fire retardant coating according to claim 1, characterized in that: The water-based acrylic resin includes an anionic methacrylic acid emulsion, and the viscosity of the emulsion at 25° C. is 5-50 mPa·s.

5. The transparent intumescent fire retardant coating according to claim 1, characterized in that: The filler includes at least one of zinc borate, magnesium hydroxide, and magnesium aluminum silicate.

6. The transparent intumescent fire retardant coating according to claim 1, characterized in that: The filler further comprises at least one of nano-montmorillonite and fumed silica.

7. The transparent intumescent fire retardant coating according to claim 6, characterized in that: The filler comprises nano-montmorillonite and fumed silica, and the mass ratio of the nano-montmorillonite to the fumed silica is 1:(0.05-0.5).

8. A method for preparing a transparent intumescent fire retardant coating according to any one of claims 1 to 7, characterized in that: The following steps are involved: After deionized water, a dispersant and a defoamer are mixed uniformly to obtain a mixed solution, an acid source, a carbon source, a gas source and a filler are added to the mixed solution and mixed uniformly to obtain a pre-dispersion solution; Mixing a water-based acrylic resin with a film-forming aid and a leveling agent to obtain a resin mixed solution; Add the resin mixed solution into the pre-dispersion solution, add the UV absorber, and stir evenly.

9. A use of the transparent intumescent fire retardant coating according to claim 1, characterized in that: Used for coating the surface of wood, bamboo or fiber products.

10. The use of the transparent intumescent fire retardant coating according to claim 9, characterized in that: The dry film thickness of the coating is 300-600 μm.

Images