Waterproof and fireproof coatings for special humid environments and with high flame retardancy, and their preparation method.

Abstract

This invention discloses a highly efficient flame-retardant waterproof and fireproof coating for use in special humid environments and its preparation method, relating to the field of waterproof and fireproof coating technology. The waterproof and fireproof coating is made from a composite base material, a composite flame retardant, a nano-waterproofing agent, a moisture-proofing agent, functional fillers, and mixed additives. This invention synergistically enhances the coating's adhesion and flexibility through an interpenetrating molecular chain network, and combines a core-shell structured nano-waterproofing agent to achieve dual protection with a superhydrophobic surface and a dense barrier layer. A molecular-level moisture barrier is constructed using double-intercalated modified bentonite, effectively inhibiting water vapor penetration. Based on a ternary synergistic flame-retardant system, a highly efficient expanded char layer is formed through coating modification and a eutectic structure, significantly enhancing the coating's fire resistance limit. Furthermore, the functional filler, through multi-level structural design and surface modification, strengthens mechanical properties and the synergistic flame-retardant effect. Combined with gradient polymerization and radiation curing processes to optimize the crosslinking network density, this ultimately overcomes the performance degradation bottleneck of traditional coatings in humid environments.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waterproof and fireproof coatings, in particular to a waterproof and fireproof coating for special humid environments and high-efficiency fire retardation and a preparation method thereof. BACKGROUND

[0002] Coatings refer to a material coated on the surface of an object and capable of forming a continuous and firm film after a certain period of time, which is a multi-component functional material that forms a continuous solid film with protection, decoration or special functions on the surface of an object through coating construction. The main purpose and function of coatings include preventing the surface of an object from being damaged by corrosion, rust, mold, insect damage, ultraviolet radiation, chemical substance corrosion, mechanical wear and tear, etc., and prolonging the service life of the coated object, as well as waterproofing, fireproofing and insulation, etc.

[0003] Waterproof and fireproof coatings refer to special coatings that have both waterproof (water-resistant, anti-permeable) and fireproof (flame-retardant, fire-resistant) core functions. Through special formula design, such coatings can form a protective layer on the surface of an object that has both sealing and fireproof properties, meeting the needs of scenarios that have dual requirements for waterproof performance and fire safety. They are key materials for modern building safety, achieving the characteristics of no leakage and no combustion in fire through technological compounding.

[0004] Existing waterproof and fireproof coatings generally have problems such as water absorption expansion, flame retardation efficiency decay and interface delamination. In special humid environments, they are prone to key defects such as decreased adhesion, mutual restriction of fire retardation and waterproof performance, and insufficient weather resistance of the coating layer. This results in the inability of the coatings to maintain stable performance in humid or harsh environments, limiting their application range. Therefore, the present application proposes a waterproof and fireproof coating for special humid environments and high-efficiency fire retardation and a preparation method thereof to solve the problems existing in the prior art. SUMMARY

[0005] To solve the above problems, the present application proposes a waterproof and fireproof coating for special humid environments and high-efficiency fire retardation and a preparation method thereof to solve the problems of existing waterproof and fireproof coatings in special humid environments, such as decreased adhesion, mutual restriction of fire retardation and waterproof performance, and insufficient weather resistance of the coating layer.

[0006] To achieve the purpose of the present application, the following technical solution is used: a waterproof and fireproof coating for special humid environments and high-efficiency fire retardation, comprising the following raw materials by weight: 40-60 parts of a composite base, 15-25 parts of a composite flame retardant, 8-15 parts of a nano waterproof agent, 5-10 parts of a moisture-proof aid, 10-20 parts of a functional filler and 2-5 parts of a mixing aid.

[0007] The composite base is a composite system of water-based epoxy resin and silicone-modified acrylic resin, the mass ratio of the water-based epoxy resin and the silicone-modified acrylic resin is 3-5:1; the composite flame retardant is composed of nano aluminum hydroxide, ammonium polyphosphate and zinc borate in a ratio of 2:1:0.5; the moisture-proof auxiliary agent is a composite of silane coupling agent and modified bentonite, the mass ratio of the silane coupling agent and the modified bentonite is 1:50.

[0008] Further improvement lies in that the nano waterproof agent is fluorosilane-modified silicon dioxide nanoparticles, the surface of the fluorosilane-modified silicon dioxide nanoparticles is coated with an Al2O3 transition layer by atomic layer deposition technology, and is coated with organic silicon resin microspheres in a core-shell structure, and the organic silicon resin microspheres internally load 5-8% of nano zirconium phosphate flame retardant synergist.

[0009] Further improvement lies in that the silane coupling agent in the moisture-proof auxiliary agent is a mixture of γ-aminopropyl triethoxysilane and isobutyl triethoxysilane, the mass ratio of the γ-aminopropyl triethoxysilane and the isobutyl triethoxysilane is 1:2, and 15% of vinyl trimethoxysilane is additionally added as a crosslinking promoter, the modified bentonite is first subjected to primary intercalation by using cetyltrimethylammonium bromide, and then subjected to secondary intercalation by introducing 3-aminopropyl trimethoxysilane through an ultrasonic-assisted impregnation method.

[0010] Further improvement lies in that the functional filler is composed of flaky mica powder, porous silica microspheres and fumed white carbon black in a mass ratio of 5:3:2; the porous silica microspheres load a flame retardant synergist, and the fumed white carbon black is grafted with silicofluorine on the surface.

[0011] Further improvement lies in that the mixing auxiliary agent includes the following raw materials in parts by weight: 0.3-0.8 parts of a defoaming agent, 0.5-1.2 parts of a leveling agent, 0.5-1.5 parts of a thickening agent, 0.7-1.5 parts of a curing agent, and 0.2-0.5 parts of a light stabilizer; the defoaming agent is selected from silicone-based defoaming agents, the leveling agent is selected from fluorocarbon-modified polyacrylates, the thickening agent is selected from associative polyurethane thickeners, the curing agent is selected from modified polyamine curing agents, and the light stabilizer is selected from benzotriazole ultraviolet absorbers.

[0012] Further improvement lies in that the specific preparation method of the silicone-modified acrylic resin includes the following steps:

[0013] S1, mixing acrylic ester monomers and organic silicon monomers containing double bonds in a molar ratio of 4:1 to prepare a prepolymer mixture;

[0014] S2, performing free radical polymerization in three stages at 60-85°C by using a gradient temperature rising polymerization process to prepare an acrylic copolymer;

[0015] S3, grafting modification is carried out to the acrylic copolymer by adding 1% by weight of epoxy silane coupling agent to the acrylic copolymer, and the organic silicon modified acrylic resin is prepared.

[0016] The preparation method of the waterproof and fireproof coating for special humid environment and high-efficiency fire resistance comprises the following steps:

[0017] Step one: the composite base material and the composite flame retardant are dispersed at high speed under vacuum condition to prepare a mixture;

[0018] Step two: the nano waterproof agent and 50% of the functional filler are added to the mixture, and a planetary ball mill is used to grind under argon protection to prepare a grinding material;

[0019] Step three: the moisture-proof auxiliary agent, the remaining 50% of the functional filler and the mixing auxiliary agent are sequentially added to the grinding material, and are dispersed under ultrasonic assistance to prepare a coating semi-product;

[0020] Step four: the pH of the coating semi-product is adjusted to 8.5-9.5 for aging, and the waterproof and fireproof coating product is prepared after aging.

[0021] Further improvement lies in that in the step four, the aging process adopts programmed temperature control: the temperature is raised to 50 DEG C at a rate of 0.5 DEG C / min for 8h, then the temperature is lowered to 35 DEG C at a rate of 0.3 DEG C / min for 8h, and electron beam irradiation treatment is adopted after aging.

[0022] The waterproof and fireproof coating product has the advantages that the organic silicon modified resin and the epoxy resin composite system are integrated, the coating adhesion and flexibility are improved through the molecular chain interpenetrating network, the super-hydrophobic surface and the dense barrier layer are realized through the combination of the core-shell structure nano waterproof agent, the molecular level moisture-proof barrier is constructed through the double intercalation modification bentonite, the water vapor permeation can be effectively inhibited, the fire resistance limit of the coating can be significantly enhanced through the high-efficiency intumescent carbon layer formed by the coating modification and eutectic structure based on the ternary synergistic flame retardant system, the mechanical properties and the flame retardant synergistic effect are strengthened through the multi-stage structure design and surface modification of the functional filler, the crosslinking network density is optimized through the gradient polymerization and irradiation curing process, and finally the performance attenuation bottleneck of the traditional coating in the humid environment is broken through, the high-efficiency fire resistance and the waterproof and moisture-proof performance in the special humid environment are realized, and the performance can be kept stable in the humid or harsh environment. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a preparation method flowchart of the long-acting durable waterproof coating with self-repairing function. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0025] Waterproof and fireproof coatings are important protective materials in the fields of construction and industry. Waterproof coatings mainly use polyurethane, acrylic or cement-based materials, block water penetration through film formation, have high ductility, strong weather resistance and other characteristics, and are suitable for humid environments such as basements and bathrooms. New products are mostly environmentally friendly, such as low-VOC water-based formulations.

[0026] Fireproof coatings are divided into intumescent and non-intumescent types: the former foams to form a honeycomb heat insulation layer when exposed to fire (such as epoxy resin-based), and the latter relies on ingredients such as vermiculite and aluminum hydroxide to directly block fire (commonly used in steel structures). Some composite coatings combine the dual functions of waterproofing and fireproofing, using silicate / polymer matrices, and through the synergistic effect of nanometer flame retardants and hydrophobic molecules, they can maintain high protection efficiency at high temperatures of 1200°C for a long time, and are widely used in tunnels, cable bridge frames and other scenes.

[0027] It should be noted that the technical means not described in detail in the embodiments of the present application can be realized by conventional means, which is not the key point of the invention, and will not be described here.

[0028] Embodiment 1

[0029] The present embodiment provides a waterproof and fireproof coating for special humid environments and efficient flame retardation, which comprises the following raw materials by weight: 40 parts of a composite base, 15 parts of a composite flame retardant, 8 parts of a nano waterproof agent, 5 parts of a moisture-proof auxiliary agent, 10 parts of a functional filler, and 2 parts of a mixing auxiliary agent. The composite base is a composite system of water-based epoxy resin and silicone-modified acrylic resin, with a mass ratio of 3:1, and a solid content of ≥50%. The water-based epoxy resin has excellent adhesion and chemical resistance, and the silicone-modified acrylic resin imparts good weather resistance and flexibility to the coating. This composite system enables the coating to maintain good physical properties and adhesion in humid environments. The epoxy equivalent weight of the water-based epoxy resin in the composite base is 450 g / eq, and the siloxane content of the silicone-modified acrylic resin is 18 wt%.

[0030] The composite flame retardant is composed of nano aluminum hydroxide, ammonium polyphosphate and zinc borate in a ratio of 2:1:0.5. The nano aluminum hydroxide is coated with stearic acid (coating rate ≥85%), and the ammonium polyphosphate and zinc borate are melt-blended to form a eutectic structure (melting point ≥280°C). At high temperatures, the composite flame retardant can decompose and absorb heat, release inert gas, form a heat-insulating carbon layer, and interrupt the combustion chain reaction, achieving efficient flame retardation.

[0031] The moisture-proof assistant is a compound of silane coupling agent and modified bentonite, and the mass ratio of the two is 1:50.

[0032] In this embodiment, the nano waterproofing agent is fluorosilane-modified silica nanoparticles with a particle size of 20-50 nm and a surface contact angle ≥ 150°. The surface of the fluorosilane-modified silica nanoparticles is coated with a 2 nm thick Al2O3 transition layer through atomic layer deposition (ALD) technology, forming an Al2O3 / SiO2 double-shell structure, and the water vapor transmission rate is reduced to ≤ 0.5 g / (m 2 ·24h). The fluorosilane-modified silica nanoparticles are coated with silicone resin microspheres in a core-shell structure, and the silicone resin microspheres internally load 5% by mass of nano-sized zirconium phosphate flame retardant synergist. This structure significantly improves the waterproof performance of the coating, prevents moisture penetration, and adapts to special humid environments. The specific implementation method is as follows:

[0033] 1) Preparation of fluorosilane-modified silica nanoparticles

[0034] Silane coupling agent treatment: The surface of the silica nanoparticles is modified using a fluorosilane coupling agent to form fluorosilane-modified silica nanoparticles. This step endows the nanoparticles with superhydrophobic properties and improves their dispersibility and compatibility in organic media.

[0035] 2) Atomic layer deposition (ALD) coating of Al2O3 transition layer

[0036] Surface cleaning: The fluorosilane-modified silica nanoparticles are subjected to surface cleaning to remove impurities and contaminants, ensuring the smooth progress of the ALD process.

[0037] ALD equipment preparation: The cleaned nanoparticles are placed in an ALD reactor, vacuumed or inert gas is introduced, and air and moisture are excluded.

[0038] ALD cycle deposition: In a vacuum or inert atmosphere, ALD cycles are used to alternately introduce Al2O3 precursors (such as trimethylaluminum) and oxidizing agents (such as water vapor). Each cycle deposits about 0.1 nm of Al2O3 film. By precisely controlling the number of cycles, a thickness of 2 nm is achieved.

[0039] Temperature control: The reaction temperature should be strictly controlled during the ALD process within the range of 150-300°C to ensure the uniformity and quality of the film.

[0040] 3) Preparation of silicone resin microspheres and loading of flame retardants

[0041] Microsphere synthesis: Silicone resin microspheres are prepared as coating materials, providing good mechanical properties and thermal stability.

[0042] Flame retardant loading: 5% by mass of nano-sized zirconium phosphate flame retardant synergist is loaded inside the silicone resin microspheres. Zirconium phosphate, as a flame retardant, can release non-flammable gas during combustion to form a heat insulation layer and improve the flame retardant effect;

[0043] 4) Construction of core-shell structure

[0044] Coated nanoparticles: Fluorosilane-modified silica nanoparticles (with an Al2O3 transition layer) are used as the core, and silicone resin microspheres are coated through physical or chemical methods to form a core-shell structure.

[0045] In this embodiment, the silane coupling agent in the moisture-proof aid is a mixture of γ-aminopropyl triethoxysilane and isobutyl triethoxysilane with a mass ratio of 1:2, and 15% of vinyl trimethoxysilane is additionally added as a crosslinking promoter;

[0046] The modified bentonite is treated by two intercalation processes, and the specific steps are as follows:

[0047] First, hexadecyl trimethyl ammonium bromide is used for primary intercalation, and then 3-aminopropyl trimethoxysilane is introduced by ultrasonic-assisted impregnation for secondary intercalation, and the final interlayer spacing reaches 4.5 nm, and the specific surface area is increased to 380 m 2 / g;

[0048] The addition of the moisture-proof aid enhances the moisture-proof ability of the coating, reduces the water absorption rate, and improves the chloride ion shielding rate, making it suitable for humid environments.

[0049] In this embodiment, the functional filler is composed of flaky mica powder, porous silica microspheres, and fumed silica, with a mass ratio of 5:3:2. The porous silica microspheres have a pore size distribution of 10-100 nm and a porosity of ≥80%. The porous silica microspheres load flame retardant synergists (pentabromotoluene + antimony trioxide, loading amount 15%). The fumed silica surface is grafted with silfluorane (contact angle ≥145°). The flaky mica powder has a diameter-thickness ratio of ≥50. These fillers not only enhance the mechanical properties of the coating, but also improve the flame retardancy and water resistance.

[0050] In this embodiment, a five-component synergistic system is used to improve the application performance and film quality of the coating, including:

[0051] Defoamer: Silicone defoamer (polyether-modified polydimethylsiloxane, HLB value controlled at 8) 0.3 parts;

[0052] Leveling agent: Fluorocarbon-modified polyacrylate (perfluoroalkyl ethoxylate) 0.5 parts;

[0053] Thickening agent: Associative polyurethane thickening agent (hydrophobically modified alkali-swellable emulsion) 0.5 parts;

[0054] Curing agent: modified polyamine curing agent (Mannich base modified polyamide) 0.7 parts;

[0055] Light stabilizer: benzotriazole ultraviolet absorber 0.2 parts;

[0056] The silicone defoaming agent prevents the coating from generating bubbles, the fluorocarbon modified polyacrylate improves the flatness of the coating, the associated polyurethane thickening agent adjusts the viscosity of the coating, the modified polyamine curing agent promotes the curing of the coating, and the benzotriazole ultraviolet absorber improves the weather resistance of the coating.

[0057] In this embodiment, the preparation method of the silicone modified acrylic resin comprises the following steps:

[0058] S1, monomer composition: mix the acrylate monomer and the double bond containing silicone monomer at a molar ratio of 4:1 to prepare a prepolymer mixture;

[0059] S2, gradient polymerization: using gradient temperature polymerization process, free radical polymerization is carried out in three stages at 60-85℃, and acrylic copolymer is prepared, the specific gradient is as follows:

[0060] The first stage is 60℃ for 2h;

[0061] The second stage is 75℃ for 1.5h;

[0062] The third stage is 85℃ for 1h;

[0063] S3, graft modification: adding epoxy silane coupling agent to the acrylic copolymer for graft modification, the mass ratio of acrylic copolymer and epoxy silane coupling agent is 100:1, the grafting rate is controlled at 8%, the epoxy silane coupling agent is selected from γ-glycidoxypropyltrimethoxysilane, and the grafting reaction is carried out at pH=9.0.

[0064] Referring to Figure 1 , the embodiment also provides a preparation method of waterproof and fireproof coating for special humid environment and high efficient flame retardation, comprising the following steps:

[0065] Step one: first, disperse the composite base and the composite flame retardant at a high speed of 1200r / min for 30min under vacuum condition (-0.095MPa) to ensure that the components are fully mixed and bubbles are avoided;

[0066] Step two: then add the nano waterproof agent and 50% functional fillers, and grind them to a particle size D50≤5μm under argon protection by using a planetary ball mill, so as to ensure the uniform dispersion of the nano materials and improve the waterproof and flame retardation performance of the coating;

[0067] Step three: then add moisture-proof additives, the remaining 50% functional fillers and mixing aids in turn, dispersed under the assistance of ultrasonic wave at 800r / min for 20min, to prepare the coating semi-product, the use of ultrasonic wave helps the uniform dispersion of additives and fillers, and improves the comprehensive performance of the coating;

[0068] The planetary ball mill adopts zirconium oxide grinding balls, the ball-to-material ratio is 8:1, the rotation speed is 300r / min, the grinding time is 2h, and the system temperature is controlled to be not more than 45℃;

[0069] Step four: after adjusting the pH of the coating semi-product to 8.5, aging for 24h, the waterproof and fireproof coating product is prepared after aging, the aging process is carried out at 40℃ and relative humidity of 30% or less, and the temperature is programmed to be raised to 50℃ at a rate of 0.5℃ / min for 8h, and then lowered to 35℃ at a rate of 0.3℃ / min for 8h; after aging, electron beam irradiation treatment is carried out, and the irradiation dose is 15kGy, to accelerate the curing network formation.

[0070] The waterproof and fireproof coating prepared in the embodiment is tested for performance, and the results are as follows:

[0071] Moisture resistance:

[0072] Saturation humidity (40℃ / RH 95%) for 30 days: volume expansion rate ≤0.8%.

[0073] Salt spray test for 3000h: adhesion retention rate ≥90%.

[0074] Flame retardancy:

[0075] Fire resistance limit ≥120min (ISO 834 standard).

[0076] Peak heat release rate ≤65kW / m 2 (cone calorimeter test).

[0077] Waterproofness:

[0078] Dynamic water contact angle ≥152°, and rolling angle ≤3°.

[0079] Penetration depth ≤0.5mm under 1.5MPa water pressure for 168h.

[0080] Example two

[0081] The embodiment provides a waterproof and fireproof coating for special humid environment and high-efficiency fireproofing, which comprises the following raw materials in parts by weight: 60 parts of a composite base, 25 parts of a composite fire retardant, 15 parts of a nano waterproof agent, 10 parts of a moisture-proof auxiliary agent, 20 parts of functional fillers and 5 parts of a mixing auxiliary agent, wherein the composite base is a composite system of water-based epoxy resin and silicone-modified acrylic resin, the mass ratio of the two is 5:1, the solid content is greater than or equal to 50%, the water-based epoxy resin has excellent adhesion and chemical resistance, and the silicone-modified acrylic resin endows the coating with good weather resistance and flexibility; the composite system enables the coating to maintain good physical properties and adhesion in a humid environment; the epoxy equivalent weight of the water-based epoxy resin in the composite base is 500 g / eq, and the siloxane content of the silicone-modified acrylic resin is 25 wt%.

[0082] The composite fire retardant is composed of nano aluminum hydroxide, ammonium polyphosphate and zinc borate at a ratio of 2:1:0.5; the nano aluminum hydroxide is coated with stearic acid (coating rate greater than or equal to 85%); the ammonium polyphosphate and the zinc borate are melt-blended to form a eutectic structure (melting point greater than or equal to 280 DEG C); at high temperature, the composite fire retardant can decompose and absorb heat, release inert gas and form a heat-insulating carbon layer to interrupt the combustion chain reaction and achieve high-efficiency fireproofing effect.

[0083] The moisture-proof auxiliary agent is a composite of silane coupling agent and modified bentonite, and the mass ratio of the two is 1:50.

[0084] In the embodiment, the nano waterproof agent is fluorosilane-modified silicon dioxide nanoparticles with a particle size of 20-50 nm and a surface contact angle greater than or equal to 150 DEG; the surface of the fluorosilane-modified silicon dioxide nanoparticles is coated with a 3 nm-thick Al2O3 transition layer by atomic layer deposition (ALD) technology to form an Al2O3 / SiO2 double-shell structure, and the water vapor permeability of the fluorosilane-modified silicon dioxide nanoparticles is reduced to less than or equal to 0.5 g / (m 2 ·24h); the fluorosilane-modified silicon dioxide nanoparticles are coated with silicone resin microspheres in a core-shell structure, and the silicone resin microspheres internally load 8 wt% of nano zirconium phosphate flame retardant synergist; the structure significantly improves the waterproof performance of the coating and prevents water penetration, thus being suitable for special humid environments.

[0085] In the embodiment, the silane coupling agent in the moisture-proof auxiliary agent is a mixture of γ-aminopropyl triethoxysilane and isobutyl triethoxysilane with a mass ratio of 1:2, and 15% of vinyl trimethoxysilane is additionally added as a crosslinking promoter;

[0086] The modified bentonite is subjected to twice intercalation treatment, and the specific steps are as follows:

[0087] First, hexadecyl trimethyl ammonium bromide is used for primary intercalation, and then 3-aminopropyl trimethoxysilane is introduced by ultrasonic assisted immersion method for secondary intercalation, and finally the interlayer spacing reaches 5.0 nm, and the specific surface area is increased to 420 m 2 / g;

[0088] The addition of moisture-proof aids enhances the moisture-proof ability of the coating, reduces the water absorption, and improves the chloride ion shielding rate, adapting to the humid environment.

[0089] In this embodiment, the functional fillers are composed of flaky mica powder, porous silica microspheres and fumed white carbon black, and the mass ratio of the three is 5:3:2. The pore size distribution of the porous silica microspheres is 10-100 nm, and the porosity is ≥80%. The porous silica microspheres load the flame-retardant synergist (penta bromo toluene + antimony trioxide, loading amount 20%). The fumed white carbon black surface is grafted with silfluorane (contact angle ≥145°). The flaky mica powder has a diameter-thickness ratio ≥50, and the surface is treated by plasma to form a micro-nano groove structure. These fillers not only enhance the mechanical properties of the coating, but also improve the flame retardancy and water resistance.

[0090] In this embodiment, a five-component synergistic system is used to improve the application performance and coating film quality of the coating, including:

[0091] Defoaming agent: silicone defoaming agent (polyether modified polydimethylsiloxane, HLB value controlled at 12) 0.8 parts;

[0092] Leveling agent: fluorocarbon modified polyacrylate (perfluoroalkyl ethoxylate) 1.2 parts;

[0093] Thickening agent: associative polyurethane thickening agent (hydrophobically modified alkali-swellable emulsion) 1.5 parts;

[0094] Curing agent: modified polyamine curing agent (Mannich base modified polyamide) 1.5 parts;

[0095] Light stabilizer: benzotriazole ultraviolet absorber 0.5 parts;

[0096] The silicone defoaming agent prevents bubbles from forming in the coating, the fluorocarbon modified polyacrylate improves the leveling property of the coating, the associative polyurethane thickening agent adjusts the viscosity of the coating, the modified polyamine curing agent promotes the curing of the coating, and the benzotriazole ultraviolet absorber improves the weather resistance of the coating.

[0097] In this embodiment, the preparation method of the silicone modified acrylic resin includes the following steps:

[0098] S1, monomer composition: mix the acrylate monomer and the organic silicon monomer containing double bonds at a molar ratio of 4:1 to prepare a prepolymer mixture;

[0099] S2, Gradient polymerization: using gradient temperature polymerization process, free radical polymerization was carried out in three stages at 60-85℃ to prepare acrylic copolymer, and the specific gradient was as follows:

[0100] The first stage was reacted at 60℃ for 2h;

[0101] The second stage was reacted at 75℃ for 1.5h;

[0102] The third stage was reacted at 85℃ for 1h;

[0103] S3, Graft modification: adding epoxy silane coupling agent to the acrylic copolymer for graft modification, the mass ratio of acrylic copolymer and epoxy silane coupling agent was 100:1, the grafting rate was controlled at 12%, the epoxy silane coupling agent was selected from γ-glycidoxypropyltrimethoxysilane, and the grafting reaction was carried out under the condition of pH=9.5.

[0104] Referring to Figure 1 , the embodiment also provides a preparation method of waterproof and fireproof coating for special humid environment and high-efficiency flame retardation, comprising the following steps:

[0105] Step one: first, the composite base and the composite flame retardant are dispersed at a high speed of 1500r / min for 45min under vacuum condition (-0.095MPa) to ensure that the components are fully mixed and air bubbles are avoided;

[0106] Step two: then, the nano waterproof agent and 50% of the functional fillers are added, and the planetary ball mill is used to grind under argon protection until the particle size D50≤5μm, so that the uniform dispersion of the nano material is ensured and the waterproof and flame retardation performance of the coating is improved;

[0107] Step three: then, the moisture-proof aid, the remaining 50% of the functional fillers and the mixing aid are sequentially added, and are dispersed at 1000r / min for 30min under ultrasonic assistance to prepare the coating semi-product, and the use of ultrasonic wave is helpful to the uniform dispersion of the aid and the fillers and the improvement of the comprehensive performance of the coating;

[0108] The planetary ball mill uses zirconia grinding balls, the ball-to-material ratio is 8:1, the rotation speed is 300r / min, the grinding time is 3h, and the system temperature is controlled to be not more than 45℃;

[0109] Step four: after the pH of the coating semi-product is adjusted to 9.5, it is aged for 24h to prepare the waterproof and fireproof coating product, and the aging process is carried out at 50℃ and relative humidity below 30%, and the temperature is programmed as follows: the temperature is increased to 50℃ at a rate of 0.5℃ / min for 8h, and then the temperature is decreased to 35℃ at a rate of 0.3℃ / min for 8h; after aging, electron beam irradiation treatment is carried out, the irradiation dose is 20kGy, and the network formation is accelerated.

[0110] The waterproof and fireproof coating prepared in the embodiment is subjected to performance test, and the results are as follows:

[0111] Moisture resistance:

[0112] Saturation humidity (40℃ / RH 95%) for 30 days: volume expansion rate ≤0.8%.

[0113] Salt spray test for 3000h: adhesion retention rate ≥90%.

[0114] Flame resistance:

[0115] Fire resistance limit ≥120min (ISO 834 standard).

[0116] Peak heat release rate ≤65kW / m 2 (cone calorimeter test).

[0117] Water resistance:

[0118] Dynamic water contact angle ≥152°, and rolling angle ≤3°.

[0119] Penetration depth ≤0.5mm under 1.5MPa water pressure for 168h.

[0120] The silicone modified resin and the epoxy resin are synergized to ensure mechanical properties and improve weather resistance, the core-shell structure nano waterproof agent realizes the dual mechanism of super-hydrophobicity and penetration barrier, the interlayer insertion structure of modified bentonite forms a molecular level moisture barrier, the waterproof and fireproof coating has excellent flame resistance and good water resistance through the synergistic effect of the composite base material, the composite flame retardant, the nano waterproof agent and the like, efficient flame resistance, waterproofness and moisture resistance are realized in special humid environment, and the performance is stable in humid or harsh environment.

[0121] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement and the like within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A water-proof fire-proof paint for special humid environment and high efficient fire retardant, characterized in that, The composite base is a composite system of water-based epoxy resin and silicone-modified acrylic resin, the mass ratio of the water-based epoxy resin and the silicone-modified acrylic resin is 3-5:1; the composite flame retardant is composed of nano aluminum hydroxide, ammonium polyphosphate and zinc borate at a ratio of 2:1:0.5; the moisture-proof additive is a composite of silane coupling agent and modified bentonite, the mass ratio of the silane coupling agent and the modified bentonite is 1:50; The nano waterproof agent is a fluorosilane modified silicon dioxide nanoparticle, the surface of the fluorosilane modified silicon dioxide nanoparticle is coated with an Al2O3 transition layer by atomic layer deposition technology, and is coated with an organic silicon resin microsphere in a core-shell structure, and the organic silicon resin microsphere internally loads a mass fraction of 5-8% of a nano zirconium phosphate flame retardant synergist; The silane coupling agent in the moisture-proof additive is a mixture of γ-aminopropyl triethoxysilane and isobutyl triethoxysilane, the mass ratio of the γ-aminopropyl triethoxysilane and the isobutyl triethoxysilane is 1:2, and 15% of vinyl trimethoxysilane is additionally added as a crosslinking promoter, the modified bentonite is first subjected to primary intercalation by using cetyltrimethylammonium bromide, and then subjected to secondary intercalation by introducing 3-aminopropyl trimethoxysilane through an ultrasonic assisted impregnation method; The functional filler is composed of flaky mica powder, porous silica microspheres and fumed silica in a mass ratio of 5:3:2; the porous silica microspheres load a flame retardant synergist, and the fumed silica surface is grafted with silfluorane; The specific preparation method of the silicone-modified acrylic resin comprises the following steps: S1, mixing acrylate monomers and organic silicon monomers containing double bonds at a molar ratio of 4:1 to prepare a prepolymer mixture; S2, using a gradient temperature polymerization process, free radical polymerization is carried out in three stages at 60-85℃ to prepare an acrylic copolymer; S3, adding 1% by weight of epoxy silane coupling agent to the acrylic copolymer for graft modification to prepare a silicone-modified acrylic resin. The mixing aid includes the following raw materials by weight: 0.3-0.8 parts of defoaming agent, 0.5-1.2 parts of leveling agent, 0.5-1.5 parts of thickening agent, 0.7-1.5 parts of curing agent and 0.2-0.5 parts of light stabilizer; the defoaming agent is selected from silicone-based defoaming agents, the leveling agent is selected from fluorocarbon-modified polyacrylates, the thickening agent is selected from associative polyurethane thickeners, the curing agent is selected from modified polyamine curing agents, and the light stabilizer is selected from benzotriazole ultraviolet absorbers.

2. The water-proof and fire-proof paint for special humid environment and high efficient fire-retardant according to claim 1, characterized in that, The method comprises the following steps:

3. A process for the preparation of a water-proof and fire-proof paint for special humid environments and highly efficient fire-retardant according to any of claims 1-2, characterized by, Step one: dispersing the composite base and the composite flame retardant at high speed under vacuum conditions to prepare a mixture; Step two: adding the nano waterproof agent and 50% of the functional filler to the mixture, and grinding with a planetary ball mill under argon protection to prepare a ground material; ​ Step three: add moisture-proof aid, the rest 50% functional filler and mixing aid into the grinding material in turn, disperse under the assistance of ultrasonic wave to obtain the coating semi-product; Step four: adjust the pH of the coating semi-product to 8.5-9.5 and mature, and then obtain the waterproof and fireproof coating product.

4. A process for the preparation of a water proof fire retardant coating for special damp environment and highly effective flame retardant as claimed in claim 3, wherein: In the step four, the temperature is controlled by program during the maturation process: the temperature is increased to 50℃ at a rate of 0.5℃ / min and kept for 8h, then decreased to 35℃ at a rate of 0.3℃ / min and kept for 8h, and then the maturation product is treated by electron beam irradiation.

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