High-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating and preparation method thereof

Abstract

The invention discloses a high-tolerance organosilicon elastic styrene-acrylic emulsion interior wall coating and a preparation method thereof, and belongs to the technical field of interior wall coatings. According to the present invention, the innovative combination design and the synergistic effect of the organosilicon-styrene-acrylic core-shell structure emulsion, the photocatalytic composite mineral filler, the functional filler, the modified cellulose nanometer fibril, the plant source reaction type film forming auxiliary agent, the composite slow-release mildewproof component and the pigment filler are adopted; the prepared high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating simultaneously realizes high elasticity, high hardness, long-acting antibacterial and mildew-proof effects, root odor removal, efficient and lasting formaldehyde purification and excellent storage stability. In addition, the selected (especially a preferable scheme) organic silicon-styrene-acrylic core-shell structure emulsion has excellent elastic-tough balance and intrinsic antibacterial property.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of interior wall coatings, and particularly relates to a high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating and a preparation method thereof. BACKGROUND

[0002] At present, interior wall coatings, as the main material for indoor decoration, directly determine the comfort, aesthetic level and health level of the living environment in terms of comprehensive performance. With the continuous rise in the public's concern for environmental protection and health, the market has put forward higher requirements for the functionality of coatings: not only basic decoration and protection, but also one or more composite functions such as anti-cracking, high elasticity, antibacterial and mildew-proof, decomposition of formaldehyde, odor removal and low toxicity.

[0003] However, in the pursuit of the above high-performance goals, the prior art often falls into multiple bottlenecks, and it is difficult to balance the inherent contradictions between various performances.

[0004] In terms of mechanical properties, in order to improve the elasticity of the coating film to cover the cracks in the base layer, the amount of elastic monomer usually needs to be increased, but this inevitably reduces the hardness of the paint film and makes the surface sticky, thereby reducing the resistance to contamination and weakening the practicality and durability of the product.

[0005] In terms of health functions, the challenges are still prominent: the widely used quaternary ammonium salt small molecule antibacterial agent is easy to migrate and precipitate, and has a short antibacterial effective period; if formaldehyde purification relies only on physical adsorption materials such as activated carbon or ordinary diatomite, the adsorption capacity is limited and easy to saturate, and there is a risk of secondary release; in addition, most "odor removal" products still remain in the stage of fragrance masking or physical adsorption, and have not been able to eliminate volatile organic compounds (VOC) from the chemical source.

[0006] In addition, the introduction of functional additives, combined with the poor dispersion stability of fillers or poor compatibility with emulsions, further induces sedimentation, flocculation and even demulsification during storage, resulting in deterioration of the opening effect and construction performance.

[0007] Therefore, how to break through the shackles of the prior art from the source of material design and the mechanism of action, and systematically integrate and balance multiple high-performance requirements, has become a core problem to be solved in the field of interior wall coatings. SUMMARY

[0008] The purpose of the present application is to solve the problems existing in the prior art, and to provide a high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating and a preparation method thereof. The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating simultaneously realizes high elasticity, high hardness, long-acting antibacterial and mildew-proof, root odor removal, high-efficiency and long-lasting formaldehyde purification, and excellent storage stability through the innovative combination design and synergistic effect of the components. In addition, the organic silicon-styrene-acrylic core-shell structure emulsion selected (especially the preferred scheme) has excellent elastic-tough balance and inherent antibacterial properties.

[0009] To solve the above problems, the present application is realized by the following technical solutions: The first invention of the present application is to: Provide a high resistance organic silicon elastic styrene-acrylic emulsion interior wall paint, which comprises the following weight parts of raw material components: Organic silicon-styrene-acrylic core-shell structure emulsion 25-40 parts, photocatalytic composite mineral filler 10-20 parts, modified cellulose nanofibril 0.5-2.0 parts, plant source reactive film forming aid 1.0-3.0 parts, composite slow-release mildew-proof component 1.0-3.0 parts, functional filler 5-10 parts, pigment 10-25 parts, additive 2.0-7.0 parts, and water in the remainder; the total weight parts of all raw material components are 100 parts; The photocatalytic composite mineral filler is porous diatomite loaded with tungsten-doped titanium dioxide (W-TiO2); the loading amount of the tungsten-doped titanium dioxide is 5%-15% by weight; The abundant multi-stage pore structure of diatomite provides its huge high specific surface area, which can efficiently physically adsorb small molecule pollutants such as formaldehyde; the tungsten-doped titanium dioxide can be excited to have photocatalytic activity in the visible light region, and completely oxidize the organic matters such as formaldehyde enriched in the pore channels of diatomite into CO2 and H2O, forming a closed-loop purification mechanism of "adsorption-concentration-degradation", which overcomes the disadvantage of easy saturation of pure physical adsorption. In addition, the mineral properties of diatomite endow it with excellent interface compatibility and bonding strength with inorganic substrates.

[0010] The modified cellulose nanofibril is obtained by hydrophobic modification of cellulose nanofibril (CNF) with a silane coupling agent; The modified cellulose nanofibril can form a stable three-dimensional network structure in water, efficiently preventing the settlement of fillers and pigments, and greatly improving the storage stability. During the film forming process, they are intertwined inside the paint film, playing a significant reinforcing role. The surface hydrophobic modification ensures its compatibility with the organic silicon-styrene-acrylic emulsion, avoiding the decrease of water resistance of the paint film caused by strong hydrophilicity.

[0011] The organic silicon-styrene-acrylic core-shell structure emulsion is prepared by a seed emulsion polymerization method, and has a core-shell structure, including a core layer and a shell layer. The end-vinyl polydimethylsiloxane is introduced into the core layer; and the methacryloyloxyethyl hexadecyl dimethyl ammonium chloride is introduced into the shell layer.

[0012] The further optimization of the high resistance organic silicon elastic styrene-acrylic emulsion interior wall paint of the present application is: The plant source reactive film forming aid is diethyl itaconate.

[0013] Unlike traditional coalescing aids which only physically plasticize, the double bond in the diethyl itaconate molecule can participate in copolymerization during the emulsion film forming process, permanently bonding into the paint film network. This achieves true zero volatile organic compound release and eliminates the odor generated by the volatilization of the aid from the source, which is the key to achieving "pure taste". Its reaction characteristics also avoid the brittleness of the paint film performance caused by the loss of the aid later.

[0014] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint further optimized in the application is: The composite slow-release mildew-proof component is a composite material with mesoporous silica microspheres as carriers and plant source mildew-proof agents loaded therein, wherein the plant source mildew-proof agent loading is 25-45% by weight.

[0015] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint further optimized in the application is: The plant source mildew-proof agent is zinc ricinoleate.

[0016] The porous silica microspheres act as "micro-reservoirs" and load the mildew-proof agents through physical adsorption. When the environmental humidity changes, the microspheres can intelligently control the release rate of the mildew-proof agents, avoid the waste caused by the initial explosive release and the failure in the later period, and thus greatly prolong the mildew-proof duration. Zinc ricinoleate as a plant source mildew-proof agent is environmentally friendly and solves the problem of easy migration after being combined with the carrier.

[0017] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint further optimized in the application is: The functional filler is at least one of mica powder with a sheet structure and calcined kaolin with a sheet structure; the calcined kaolin with a sheet structure is calcined kaolin calcined at 700-800 DEG C.

[0018] The sheet-shaped fillers are arranged in parallel in the paint film to form a dense physical barrier. On the one hand, they can effectively block the penetration of water vapor, corrosive media and molecules such as formaldehyde, and improve the water resistance and shielding property of the coating film; on the other hand, the hard sheet structure like "steel bars" cooperates with the elastic emulsion to enhance the tensile strength and tear resistance of the paint film, further consolidating the anti-cracking effect.

[0019] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint further optimized in the application is: The silane coupling agent is gamma-aminopropyl triethoxysilane (KH-550).

[0020] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint further optimized in the application is: The pigments and fillers include one or a combination of rutile titanium dioxide and heavy calcium carbonate. The auxiliary agent includes one or a combination of several of wetting agent, dispersant, defoaming agent, thickening agent, covering polymer, wax emulsion, antiseptic fungicide.

[0021] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint is further optimized as follows: The organic silicon-styrene-acrylic core-shell structure emulsion is prepared by a seed emulsion polymerization method, and has a core-shell structure including a core layer and a shell layer. The core layer is formed by copolymerization of a mixture including styrene, butyl acrylate and end-vinyl polydimethylsiloxane; The shell layer is formed by copolymerization of a mixture including styrene, methyl methacrylate, gamma-methacryloxypropyltrimethoxysilane and methacryloxyethylhexadecyl dimethyl ammonium chloride; The end-vinyl polydimethylsiloxane in the core layer is connected to the gamma-methacryloxypropyltrimethoxysilane in the shell layer by hydrolytic condensation to form Si-O-Si covalent bonds.

[0022] The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall paint is further optimized as follows: The end-vinyl polydimethylsiloxane accounts for 10% to 25% of the total weight of the monomers in the core layer; The gamma-methacryloxypropyltrimethoxysilane accounts for 5% to 15% of the total weight of the monomers in the shell layer; The methacryloxyethylhexadecyl dimethyl ammonium chloride accounts for 1% to 5% of the total weight of the monomers in the shell layer.

[0023] The end-vinyl polydimethylsiloxane in the core layer copolymerizes with the styrene-acrylic polymer to endow the paint film with excellent elasticity and extremely low surface energy, thereby having good anti-cracking property and hydrophobic property. The methyl methacrylate in the shell layer endows the coating with the required surface hardness; the siloxane network formed after hydrolysis of the gamma-methacryloxypropyltrimethoxysilane (KH-570) crosslinks with the polysiloxane segment (provided by the end-vinyl polydimethylsiloxane) in the core layer through Si-O-Si covalent bonds, realizing firm bonding of the core-shell structure. This structure design of “soft inside and hard outside” enables the paint film to maintain high elasticity while having high surface hardness and strong anti-sticking property, thereby significantly improving the stain resistance.

[0024] The cationic monomer methacryloxyethyl hexadecyl dimethyl ammonium chloride introduced in the shell layer is firmly anchored to the polymer main chain through covalent bonding, and a persistent quaternary ammonium salt antibacterial layer is constructed. This structure effectively inhibits the migration and precipitation of small molecule antibacterial agents, and gives the coating long-acting and stable contact type antibacterial performance. At the same time, the introduction of γ-methacryloxypropyl trimethoxysilane (KH-570) further improves the water resistance and storage stability of the emulsion.

[0025] The high-resistance silicone-elastic styrene-acrylic emulsion interior wall coating of the application is further optimized as follows: The silicone-styrene-acrylic core-shell structure emulsion specifically includes the following components by weight: Core layer composition (parts by weight): Styrene 30-40 parts, butyl acrylate 50-60 parts, and vinyl-terminated polydimethylsiloxane 8-12 parts; Shell layer composition (parts by weight): Styrene 15-25 parts, methyl methacrylate 20-30 parts, γ-methacryloxypropyl trimethoxysilane 10-15 parts, and methacryloxyethyl hexadecyl dimethyl ammonium chloride 4-6 parts.

[0026] The second invention of the application is to: Provide a preparation method of the high-resistance silicone-elastic styrene-acrylic emulsion interior wall coating as described above, which includes the following preparation steps: s1. In a dispersing device, add part of the auxiliary agent (the part of the auxiliary agent preferably includes wetting agent, dispersing agent and 1 / 2 defoaming agent), modified cellulose nanofibril to part of the water at a speed of 300-500 rpm, and disperse for 5-15 minutes to obtain a preliminary mixture; This low-speed pre-dispersion step is designed to allow the modified cellulose nanofibril to be fully hydrated and stretched, and to pre-construct a three-dimensional network structure in water, providing a basis for efficient dispersion and stability of the subsequent fillers; s2. Increase the speed to 1000-1300 rpm, and add photocatalytic composite mineral filler, pigment filler and functional filler to the preliminary mixture, and disperse at high speed for 15-25 minutes to detect the slurry fineness to ≤50 μm; High shear force ensures that the filler and pigment aggregates are fully dispersed and uniformly embedded in the network constructed by the cellulose nanofibril, forming a stable and delicate slurry, which is a prerequisite for obtaining excellent film appearance and performance; s3. Reduce the rotation speed to 400-600 rpm, add silicone-phenylpropyl core-shell structure emulsion, plant source reactive film-forming aid, composite slow-release mildew-proof component, and the remaining part of the aid (the remaining part of the aid preferably includes thickening agent, 1 / 2 defoaming agent, wax emulsion, covering polymer, and preservative and bactericide) to the slurry obtained in step s2, and disperse for 10-20 minutes to obtain a paint mixture; This stage uses low-speed stirring, aiming to gently mix the emulsion and functional components into the well-dispersed slurry, avoiding high shear force to cause emulsion demulsification and destruction of the structure of the functional components, and ensuring the integrity of the functions of the components; s4. Adjust the viscosity of the paint mixture to 100-110 KU of Stormer viscosity with the remaining amount of water, filter, and discharge to prepare the high-resistance silicone-elastic phenylpropyl emulsion interior wall paint.

[0027] The technical solution of the present application has the following overall beneficial effects: 1. Synergistic optimization of mechanical properties, breaking through the bottleneck of traditional technology. The present application realizes effective balance of elasticity and hardness through the design of the silicone-phenylpropyl core-shell structure. The flexible silicone chain segment of the core layer endows the coating film with excellent elastic deformation ability, and the rigid crosslinked network of the shell layer provides the necessary surface hardness. This "soft inside and hard outside" structural feature enables the coating film to maintain high elongation at break while significantly improving surface stain resistance, successfully solving the technical problem of sticky surface and easy contamination of traditional elastic coatings.

[0028] 2. Long-term stability of functional components, realizing continuous environmental purification. Based on molecular structure design and carrier complex technology, a long-term action mechanism is established. The shell layer copolymerized quaternary ammonium salt antibacterial component (including methacryloyloxyethyl hexadecyl dimethyl ammonium chloride in the shell structure) realizes permanent antibacterial effect through chemical bonding; the photocatalytic composite material continuously purifies formaldehyde through the synergistic effect of "adsorption-degradation"; and the microsphere-loaded mildew-proof component realizes intelligent slow release. These designs ensure the long-term effectiveness of environmental purification, overcoming the technical defects of easy migration and easy saturation of traditional small molecule functional agents.

[0029] 3. Source control of pollutant release, improving environmental friendliness. The reactive plant source film-forming aid is used, which is permanently fixed in the paint film network through copolymerization reaction, eliminating the release of volatile organic compounds from the source. At the same time, the selected functional components all have low volatility, and combined with effective carrier fixation technology, the product maintains extremely low volatile organic compound content during the life cycle, realizing true environmental friendliness.

[0030] 4. The system stability is significantly enhanced, ensuring the reliability of product application. By introducing surface-modified cellulose nanofibrils, a stable three-dimensional network structure is constructed in the system, effectively preventing filler sedimentation and component separation. The optimized preparation process ensures good compatibility between components, maintaining excellent stability during the storage period, with no significant changes in performance indicators, ensuring the reliability of the entire process from production to use. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be described in detail below with specific examples. It should be understood that the specific examples described herein are only used to explain the present application and are not limited to the present application. Any simple improvement to the preparation method of the present application within the concept of the present application falls within the scope of protection of the present application. Example 1

[0032] A high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating and a preparation method thereof The high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating comprises the following raw material components by weight: 35 parts of organic silicon-styrene-acrylic core-shell structure emulsion (prepared by seed emulsion polymerization), 15 parts of photocatalytic composite mineral filler, 8 parts of functional filler (calcined kaolin, calcination temperature 750℃), 1 part of modified cellulose nanofibril, 1.5 parts of plant-based reactive film-forming aid, 2 parts of composite slow-release mildew-proof component, 15 parts of pigment filler (rutile titanium dioxide), 1.4 parts of wetting agent, 0.6 parts of dispersing agent (sodium polyacrylate), 0.6 parts of defoaming agent (polyether-modified silicone oil), 0.4 parts of thickening agent (hydroxyethyl cellulose), 0.3 parts of preservative and bactericide, 0.1 parts of wax emulsion, 0.2 parts of hiding polymer, and the balance is water; the total weight of all raw material components is 100 parts; The photocatalytic composite mineral filler is porous diatomite loaded with 10% tungsten-doped titanium dioxide (W-TiO2). The modified cellulose nanofibril is surface grafted and modified cellulose nanofibril (CNF) using silane coupling agent (KH-550).

[0033] The plant-based reactive film-forming aid is diethyl itaconate.

[0034] The composite slow-release mildew-proof component uses mesoporous silica microspheres as a carrier and loads plant-based mildew inhibitor zinc ricinoleate with a loading capacity of 30%.

[0035] The preparation method of the high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating comprises the following preparation steps: s1. In a dispersing device, add wetting agent, dispersing agent, one third of defoaming agent and modified cellulose nanofibril into part of water (about 60% of the total amount) at a rotation speed of 400 rpm, disperse for 10 minutes to obtain a preliminary mixture; s2. Increase the rotation speed to 1200 rpm, add photocatalytic composite mineral filler, pigment, functional filler to the preliminary mixture, high-speed disperse for 20 minutes, detect the fineness of the slurry to ≤45 μm; s3. Reduce the rotation speed to 500 rpm, add silicone-styrene-acrylate core-shell structure emulsion, plant source reactive film-forming aid, composite slow-release mildew-proof component, thickening agent, wax emulsion, hiding polymer and the remaining defoaming agent to the slurry obtained in step s2, disperse for 15 minutes to obtain a coating mixture; s4. Adjust the viscosity of the coating mixture to Stomer viscosity 100-110 KU with the remaining water, filter and discharge to prepare the high-tolerance silicone-elastic styrene-acrylate emulsion interior wall coating.

[0036] The silicone-styrene-acrylate core-shell structure emulsion is prepared by a conventional seed emulsion polymerization method, and has a core-shell structure, including a core layer and a shell layer. The core layer is formed by copolymerization of a mixture including styrene, butyl acrylate and end-vinyl polydimethylsiloxane; The shell layer is formed by copolymerization of a mixture including styrene, methyl methacrylate, γ-methacryloyloxypropyl trimethoxysilane and methacryloyloxyethyl hexadecyl dimethyl ammonium chloride; The end-vinyl polydimethylsiloxane in the core layer is connected to the γ-methacryloyloxypropyl trimethoxysilane in the shell layer by hydrolytic condensation to form Si-O-Si covalent bonds.

[0037] The silicone-styrene-acrylate core-shell structure emulsion specifically includes the following components by weight: Core layer composition (parts by weight): Styrene 30 parts, butyl acrylate 55 parts, end-vinyl polydimethylsiloxane 10 parts; Shell layer composition (parts by weight): Styrene 15 parts, methyl methacrylate 20 parts, γ-methacryloyloxypropyl trimethoxysilane 12 parts, methacryloyloxyethyl hexadecyl dimethyl ammonium chloride 5 parts. Example 2

[0038] A high-tolerance silicone-elastic styrene-acrylate emulsion interior wall coating and a preparation method thereof The high-tolerance silicone-elastic styrene-acrylate emulsion interior wall coating includes the following raw material components by weight: 30 parts of silicone-phenylpropylene core-shell structure emulsion (prepared by seed emulsion polymerization), 12 parts of photocatalytic composite mineral filler, 10 parts of functional filler (800-mesh flaky mica powder), 1 part of modified cellulose nanofibril, 2 parts of plant source reactive film-forming aid, 1.5 parts of composite slow-release mildew-proof component, 18 parts of pigment and filler (heavy calcium carbonate, rutile titanium dioxide), 0.6 part of dispersing agent (sodium polycarboxylate), 0.4 part of wetting agent, 0.3 part of defoaming agent (polyether-modified silicone oil), 0.4 part of thickening agent (hydrophobically modified hydroxyethyl cellulose), 0.2 part of hiding polymer, 0.3 part of preservative and bactericidal agent, 0.1 part of wax emulsion, and the balance of water; the total weight parts of all raw material components are 100 parts; The photocatalytic composite mineral filler is porous diatomite loaded with 8% tungsten-doped titanium dioxide (W-TiO2). The modified cellulose nanofibril is surface grafted and modified by using a silane coupling agent (γ-aminopropyl triethoxysilane KH-550) on cellulose nanofibril (CNF).

[0039] The plant source reactive film-forming aid is diethyl itaconate.

[0040] The composite slow-release mildew-proof component takes mesoporous silica microspheres as a carrier and loads plant source mildew-proof agent zinc ricinoleate with a loading capacity of 30%.

[0041] The preparation method of the high-tolerance silicone-elastic phenylpropylene emulsion interior wall coating includes the following preparation steps: s1. In a dispersing device, add a wetting agent, a dispersing agent, and one-third of a defoaming agent to part of water (about 60% of the total amount) at a rotation speed of 350 rpm, and disperse for 12 minutes to obtain a preliminary mixture; s2. Increase the rotation speed to 1250 rpm, add a photocatalytic composite mineral filler, a functional filler, and pigment and filler (heavy calcium carbonate and rutile titanium dioxide) to the preliminary mixture, and disperse at a high speed for 22 minutes to detect the fineness of the slurry to be ≤45 μm; s3. Reduce the rotation speed to 450 rpm, add a silicone-phenylpropylene core-shell structure emulsion, a plant source reactive film-forming aid, a composite slow-release mildew-proof component, a thickening agent, a wax emulsion, a hiding polymer, and the remaining part of a defoaming agent, a preservative and bactericidal agent to the slurry obtained in step s2, and disperse for 15 minutes to obtain a coating mixture; s4. Adjust the viscosity of the coating mixture to a Stormer viscosity of 100-110 KU by using the balance of water, filter, and discharge to prepare the high-tolerance silicone-elastic phenylpropylene emulsion interior wall coating.

[0042] The preparation method of the silicone-phenylpropylene core-shell structure emulsion used in Example 2 is the same as that in Example 1, and the main difference lies in the use amount of the specific raw material components. The organic silicon-styrene-acrylic core-shell structure emulsion specifically includes the following components by weight: Core layer composition (weight parts): Styrene 35 parts, butyl acrylate 55 parts, end-vinyl polydimethylsiloxane 10 parts; Shell layer composition (weight parts): Styrene 18 parts, methyl methacrylate 25 parts, γ-methacryloyloxypropyl trimethoxysilane 12 parts, methyl methacryloyloxyethyl hexadecyl dimethyl ammonium chloride 5 parts. Example 3

[0043] A high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating and a preparation method thereof The high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating includes the following raw material components by weight: Organic silicon-styrene-acrylic core-shell structure emulsion (prepared by seed emulsion polymerization) 40 parts, photocatalytic composite mineral filler 18 parts, functional filler (calcined kaolin, calcination temperature 750°C) 10 parts, modified cellulose nanofibril 1.5 parts, plant source reactive film-forming aid 1 part, composite slow-release mildew-proof component 2.5 parts, pigment and filler (heavy calcium carbonate, rutile titanium dioxide) 12 parts, dispersing agent (sodium salt of polyacrylic acid) 0.5 parts, wetting agent 0.4 parts, defoaming agent (polyether-modified silicone oil) 0.4 parts, thickening agent (associative polyurethane) 0.3 parts, preservative and fungicide 0.3 parts, wax emulsion 0.1 parts, hiding polymer 0.2 parts, and water in the remainder; the total weight parts of all raw material components are 100 parts; The photocatalytic composite mineral filler is porous diatomite loaded with 12% tungsten-doped titanium dioxide (W-TiO2). The modified cellulose nanofibril is surface grafted and modified by using a silane coupling agent (γ-aminopropyl triethoxysilane KH-550) on cellulose nanofibril (CNF).

[0044] The plant source reactive film-forming aid is diethyl itaconate.

[0045] The composite slow-release mildew-proof component uses mesoporous silica microspheres as a carrier and loads plant source mildew-proof agent zinc ricinoleate with a loading capacity of 30%.

[0046] The preparation method of the high-resistance organic silicon elastic styrene-acrylic emulsion interior wall coating includes the following preparation steps: s1. In a dispersing device, under a rotation speed of 500 rpm, add a dispersing agent, one-third of a defoaming agent, and a modified cellulose nanofibril to part of water (about 50% of the total amount), disperse for 8 minutes, and obtain a preliminary mixture; s2. The speed is raised to 1300 rpm, and the photocatalytic composite mineral filler, functional filler, and color filler (heavy calcium carbonate, rutile titanium dioxide) are added to the preliminary mixture, and high-speed dispersion is performed for 25 minutes. The slurry fineness is detected to be ≤40 μm; s3. The speed is reduced to 400 rpm, and the silicone-styrene-acrylate core-shell structure emulsion, plant-based reactive film-forming aid, composite slow-release mildew-resistant component, thickening agent, remaining defoaming agent, hiding polymer, wax emulsion, preservative and fungicide are added to the slurry obtained in step s2, and dispersion is performed for 18 minutes to obtain a paint mixture; s4. The paint mixture viscosity is adjusted to a Stormer viscosity of 100-110 KU using the remaining water, and filtration and discharging are performed to obtain the high-tolerance silicone-elastic styrene-acrylate emulsion interior wall paint.

[0047] The preparation method of the silicone-styrene-acrylate core-shell structure emulsion used in Example 3 is the same as that of Example 1, and the main difference is that the amounts of the specific raw material components are different. The silicone-styrene-acrylate core-shell structure emulsion specifically includes the following components by weight: Core layer composition (by weight): Styrene 35 parts, butyl acrylate 52 parts, and end-vinyl polydimethylsiloxane 10 parts; Shell layer composition (by weight): Styrene 20 parts, methyl methacrylate 22 parts, γ-methacryloyloxypropyl trimethoxysilane 10 parts, and methacryloyloxyethyl hexadecyl dimethyl ammonium chloride 5 parts. Example 4

[0048] A high-tolerance silicone-elastic styrene-acrylate emulsion interior wall paint and a preparation method thereof The high-tolerance silicone-elastic styrene-acrylate emulsion interior wall paint includes the following raw material components by weight: Silicone-styrene-acrylate core-shell structure emulsion (prepared by a seed emulsion polymerization method) 28 parts, photocatalytic composite mineral filler 10 parts, functional filler A (800-mesh flaky mica powder) 5 parts, functional filler B (calcined kaolin, calcination temperature 800°C) 5 parts, modified cellulose nanofibril 1.2 parts, plant-based reactive film-forming aid 2.5 parts, composite slow-release mildew-resistant component 1 part, color filler (rutile titanium dioxide) 20 parts, dispersant (sodium polycarboxylate) 0.7 parts, wetting agent 0.4 parts, defoaming agent (polyether-modified silicone oil) 0.3 parts, thickening agent (hydrophobically modified hydroxyethyl cellulose) 0.5 parts, preservative and fungicide 0.3 parts, wax emulsion 0.1 parts, hiding polymer 0.2 parts, and water in a remainder amount; the total weight of all the raw material components is 100 parts; The photocatalytic composite mineral filler is porous diatomite loaded with 15% tungsten-doped titanium dioxide (W-TiO2). The modified cellulose nanofibril is surface grafted modified by using silane coupling agent (KH-550) on cellulose nanofibril (CNF).

[0049] The plant source reactive film-forming aid is diethyl itaconate.

[0050] The composite sustained-release mildew-proof component uses mesoporous silica microspheres as a carrier, and loads plant source mildew-proof agent zinc ricinoleate with a loading capacity of 30%.

[0051] The preparation method of the high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating comprises the following preparation steps: s1. In a dispersing device, add dispersant, half of the defoaming agent, and modified cellulose nanofibril to part of the water (about 65% of the total amount) at a rotation speed of 300 rpm, and disperse for 15 minutes to obtain a preliminary mixture; s2. Increase the rotation speed to 1000 rpm, and add the photocatalytic composite mineral filler, functional filler, and pigment filler to the preliminary mixture, and high-speed disperse (at 1100 rpm) for 18 minutes, and detect the slurry fineness to be ≤50 μm; s3. Reduce the rotation speed to 600 rpm, and add the organic silicon-styrene-acrylic core-shell structure emulsion, plant source reactive film-forming aid, composite sustained-release mildew-proof component, wetting agent, thickening agent, remaining defoaming agent, hiding polymer, wax emulsion, and preservative and bactericide to the slurry obtained in step s2, and low-speed disperse for 10 minutes to obtain a coating mixture; s4. Adjust the viscosity of the coating mixture to a Stormer viscosity of 100-110 KU by using the remaining amount of water, filter, and discharge to prepare the high-tolerance organic silicon elastic styrene-acrylic emulsion interior wall coating.

[0052] The preparation method of the organic silicon-styrene-acrylic core-shell structure emulsion used in Example 4 is the same as that in Example 1.

[0053] Comparative Example 1 Comparative Example 1 and Example 1 are basically the same in composition and preparation method, and the main difference is that: Comparative Example 1 uses a common styrene-acrylic emulsion (without core-shell structure, without organic silicon and cationic monomer) with the same glass transition temperature; instead of using modified cellulose nanofibril, conventional hydroxyethyl cellulose is used as a thickening agent; Texanol is used as a film-forming aid instead of a plant source reactive film-forming aid; talc is used instead of functional filler flaky calcined kaolin, and no photocatalytic composite mineral filler and composite sustained-release mildew-proof component are added, and the amount thereof is replaced by an equal amount of titanium dioxide and heavy calcium carbonate.

[0054] Comparative Example 2 Comparative Example 2 and Example 1 are basically the same in composition and preparation method, and the main difference is that: Comparative Example 2 also adopts a core-shell emulsion, but the shell layer of the core-shell emulsion does not introduce methacryloxyethyl hexadecyl dimethyl ammonium chloride; no composite slow-release mildew-proof component is added.

[0055] Comparative Example 3 Comparative Example 3 is basically the same as Example 1 in composition and preparation method, and the main difference is that: Comparative Example 3 does not use modified cellulose nanofilaments, and the same amount of dispersant and traditional thickener is added to make up for it; the photocatalytic composite mineral filler is replaced by an equal amount of ordinary diatomite.

[0056] The performance tests of the examples and comparative examples are shown in Table 1.

[0057] Table 1

[0058] According to the performance test results in Table 1, the comprehensive performance of the examples and comparative examples is compared and analyzed as follows: In terms of mechanical properties and surface characteristics, Examples 1-4 all exhibit excellent elongation at break (≥198%) and significant stain resistance (reflection coefficient reduction rate ≤10%), which is related to the unique design of the organic silicon-styrene-acrylic core-shell structure emulsion. The introduction of end-vinyl polydimethylsiloxane in the core layer effectively improves the flexibility of the polymer chain, and the methyl methacrylate and silane coupling agent in the shell layer build a rigid network through covalent crosslinking, thereby successfully realizing the synergistic effect of "soft inside and hard outside", making the coating film have high elasticity and high surface hardness. In contrast, Comparative Example 1 uses ordinary styrene-acrylic emulsion, and its elongation at break is only 55%, and during the application of the paint film, cracking of the paint film occurs at low temperature (5°C), and the stain resistance significantly deteriorates (the reflection coefficient reduction rate reaches 25%), fully demonstrating the key role of the core-shell structure and organic silicon modification in solving the contradiction between elasticity and stain resistance.

[0059] In terms of functionality, environmental protection and storage stability, the embodiments of the present application also show significant advantages. Embodiments 1-4 realize efficient and persistent antibacterial (inhibition rate ≥ 99.2%), formaldehyde purification (24h efficiency ≥ 85%) and mildew-proof (0 level) performance by virtue of the copolymerized quaternary ammonium salt monomer in the shell layer, the photocatalytic composite mineral filler and the composite slow-release mildew-proof component; at the same time, the use of the plant source reactive film-forming aid (diethyl itaconate) makes the VOC content undetectable, and the modified cellulose nanofilament ensures excellent storage stability of the system (sedimentation level 10, 10 representing that the powder does not settle, and 5 representing that the sedimentation is 1cm) through steric hindrance effect. Comparative Example 2 has a significant decline in antibacterial and mildew-proof performance due to the lack of bonding antibacterial and slow-release mildew-proof mechanism; Comparative Example 3 has a sharp decline in formaldehyde purification efficiency and persistence after replacing the photocatalytic composite material with ordinary diatomite; Comparative Examples 1 and 3 have obvious sedimentation and serious storage stability due to the non-use of modified cellulose nanofilament. The above comparative results inversely verify the indispensability of various functional components (such as part of the rheological effect of the thickening agent) and the synergistic mechanism thereof in the present application, indicating that the present application successfully realizes the internal unity and long-term stability of multiple high-performance.

[0060] In summary, the above-mentioned embodiments are only preferred examples of the present application, and do not limit the present application in any form; any slight changes, modifications and equivalent changes made by those skilled in the art within the scope of the technical solutions of the present application, using the disclosed technical content, are considered equivalent examples of the present application; at the same time, any equivalent changes, modifications and evolution of the above-mentioned embodiments according to the essential technology of the present application are within the protection scope of the technical solutions of the present application.

[0061] The technical features of the above-mentioned embodiments can be combined arbitrarily, and in order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described, however, as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0062] Unless otherwise specified, the experimental methods in the present application are usually carried out according to the conventional conditions or the conditions recommended by the manufacturers.

[0063] Unless otherwise specified, the various optimized technical solutions in the present application can be combined with each other.

[0064] Unless otherwise specified, the percentages and parts are weight percentages and weight parts.

[0065] Unless otherwise specified, the experimental methods in the present application are usually carried out according to the conventional conditions or the conditions recommended by the manufacturers.

[0066] Various starting materials, reagents, components, and the like, used in the present application are those known in the art and are commercially available unless otherwise indicated.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Furthermore, all methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application.

Claims

1. A high-resistance silicone elastic styrene-acrylic emulsion interior wall coating, characterized in that: It comprises the following raw material components in parts by weight: The composition comprises: 25-40 parts of organosilicon-phenylene propylene core-shell emulsion; 10-20 parts of photocatalytic composite mineral filler; 0.5-2.0 parts of modified cellulose nanofibers; 1.0-3.0 parts of plant-derived reactive film-forming aid; 1.0-3.0 parts of composite slow-release antifungal component; 5-10 parts of functional filler; 10-25 parts of pigments and fillers; 2.0-7.0 parts of additives; and water as the balance. The total weight of all raw material components is 100 parts. The photocatalytic composite mineral filler is porous diatomaceous earth loaded with tungsten-doped titanium dioxide; the loading amount of the tungsten-doped titanium dioxide is 5% to 15% by weight. The modified cellulose nanofibers were obtained by surface hydrophobic modification of cellulose nanofibers using a silane coupling agent; The organosilicon-styrene-propyl core-shell emulsion is prepared by seed emulsion polymerization and has a core-shell structure, including a core layer and a shell layer. The core layer contains terminal vinyl polydimethylsiloxane; the shell layer contains methacryloyloxyethylhexadecyldimethylammonium chloride.

2. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The plant-derived reactive film-forming aid is diethyl itaconic acid.

3. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The composite slow-release antifungal component is a composite material with mesoporous silica microspheres as carriers and loaded with plant-derived antifungal agents, wherein the loading of plant-derived antifungal agents is 25-45% by weight.

4. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 3, characterized in that: The plant-derived antifungal agent is zinc ricinoleate.

5. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The functional filler is at least one of mica powder with a sheet-like structure and calcined kaolin with a sheet-like structure; the calcined kaolin with a sheet-like structure is calcined kaolin calcined between 700 and 800°C.

6. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The silane coupling agent is γ-aminopropyltriethoxysilane.

7. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The pigments and fillers mentioned include one or a combination of rutile titanium dioxide and heavy calcium carbonate; The additives include one or a combination of several of the following: wetting agents, dispersants, defoamers, thickeners, covering polymers, wax emulsions, and preservatives and bactericides.

8. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: The organosilicon-styrene-propyl core-shell emulsion is prepared by seed emulsion polymerization and has a core-shell structure, including a core layer and a shell layer. The core layer is formed by copolymerization of a mixture comprising styrene, butyl acrylate and vinyl-terminated polydimethylsiloxane; The shell is formed by copolymerization of a mixture comprising styrene, methyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane and methacryloyloxyethylhexadecyldimethylammonium chloride; The terminal vinyl polydimethylsiloxane in the core layer and the γ-methacryloyloxypropyltrimethoxysilane in the shell layer are connected by hydrolysis and condensation to form Si-O-Si covalent bonds.

9. The high-resistance silicone elastic styrene-acrylic emulsion interior wall coating according to claim 8, characterized in that: The amount of the terminal vinyl polydimethylsiloxane is 10% to 25% of the total weight of the monomers in the core layer; The amount of γ-methacryloyloxypropyltrimethoxysilane used accounts for 5% to 15% of the total weight of the monomers in the shell layer; The amount of the methacryloyloxyethylhexadecyl dimethyl ammonium chloride used accounts for 1% to 5% of the total weight of the monomers in the shell.

10. A method for preparing the high-resistance organosilicon elastic styrene-acrylic emulsion interior wall coating according to claim 1, characterized in that: It includes the following preparation steps: s1. In a dispersion device, at a speed of 300-500 rpm, add a portion of the additive to a portion of the water to modify the cellulose nanofibers, disperse for 5-15 minutes to obtain a preliminary mixture; s2. Increase the rotation speed to 1000-1300 rpm, add photocatalytic composite mineral filler, pigments, and functional fillers to the preliminary mixture, disperse at high speed for 15-25 minutes, and check the fineness of the slurry to ≤50μm; s3. Reduce the rotation speed to 400-600 rpm, add organosilicon-styrene core-shell structure emulsion, plant-derived reactive film-forming aid, composite slow-release antifungal component, and the remaining additives to the slurry obtained in step s2, and disperse for 10-20 minutes to obtain a coating mixture; s4. Adjust the viscosity of the coating mixture to a Stormer viscosity of 100-110 KU using the remaining water, filter and discharge to prepare the high-resistance organosilicon elastic styrene-acrylic emulsion interior wall coating.

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