Multifunctional water-based paint for interior wall and preparation method of multifunctional water-based paint

Abstract

The invention relates to the technical field of water-based paint, in particular to multifunctional water-based paint for an interior wall and a preparation method of the multifunctional water-based paint. 15 to 20 parts of an acrylate emulsion; 20 to 25 parts of modified diatomite; 10 to 15 parts of kaolin subjected to surface treatment; 5-8 parts of modified talcum powder; 1 to 1.5 parts of dipropylene glycol monobutyl ether; 1 to 1.5 parts of glycerol butyl ether acetate; 0.5 to 1 part of organic silicon modified polyacrylate; 0.5 to 1 part of a fluorocarbon surfactant; 0.2 to 0.5 part of a defoaming agent; 0.3 to 0.6 part of a wetting agent; 0.5 to 1.5 parts of a thickening agent ASE-60; 0.1 to 0.2 part of a polypropylene glycol dispersant; a benzene ring structure of the styrene-acrylic emulsion provides excellent weather resistance and mechanical strength, and carboxyl and ester groups of acrylic ester endow the system with good flexibility and adhesive force.

Description

Technical Field

[0001] The present invention relates to the technical field of water-based coatings, and in particular to a multifunctional water-based coating for interior walls and a preparation method thereof. Background Art

[0002] As people pay more and more attention to the health of indoor environment, interior wall coatings need to not only have basic decorative functions, but also meet multiple requirements such as environmental protection and functionality. At present, the interior wall coatings on the market mainly have the following problems:

[0003] First, while traditional interior wall paints offer excellent basic properties like covering and decoration, their impact on improving indoor air quality is limited. Specifically, for treating indoor pollutants like formaldehyde, existing products mostly rely on single adsorption fillers or simple physical adsorption. However, due to a weak bond between the filler and the substrate and a lack of surface active sites, the purification effect is not long-lasting and the service life is short.

[0004] Secondly, self-cleaning interior wall coatings currently on the market primarily achieve antifouling properties by adding hydrophobic components, but this presents challenges such as high cost and poor durability. In practical applications, the hydrophobic components are particularly poorly compatible with the coating matrix, easily migrating and leaching, leading to a significant degradation of hydrophobic properties over time. Furthermore, single hydrophobic modification cannot simultaneously ensure the coating's breathability, resulting in a "suffocating" effect on the wall.

[0005] Thirdly, existing multifunctional interior wall coatings often achieve this through the simple combination of multiple functional components. This approach not only increases costs but, more importantly, can interfere with each other, making it difficult to achieve synergistic benefits. For example, increasing hydrophobicity often reduces the coating's air permeability and formaldehyde adsorption performance, a technical contradiction that has yet to be effectively addressed in the prior art.

[0006] Finally, in terms of coating preparation technology, the existing technology does not pay enough attention to the surface modification and dispersion stability of fillers, which leads to problems such as filler sedimentation and agglomeration during storage and use of the coating, affecting the product's construction performance and use effect. Summary of the Invention

[0007] In view of the above problems, the present invention proposes an innovative multifunctional water-based interior wall coating formula and a preparation method thereof.

[0008] The object of the present invention is to provide a multifunctional water-based paint for interior walls, comprising the following components in parts by weight:

[0009] 30-35 parts of styrene acrylic emulsion;

[0010] 15-20 parts of acrylic emulsion;

[0011] 20-25 parts of modified diatomaceous earth;

[0012] 10-15 parts of surface treated kaolin;

[0013] 5-8 parts of modified talc;

[0014] 1-1.5 parts of dipropylene glycol monobutyl ether;

[0015] 1-1.5 parts of propylene glycol butyl ether acetate;

[0016] 0.5-1 part of silicone modified polyacrylate;

[0017] 0.5-1 part of fluorocarbon surfactant;

[0018] 0.2-0.5 parts of defoaming agent;

[0019] Wetting agent BYK-331 0.3-0.6 parts;

[0020] Thickener ASE-60 0.5-1.5 parts;

[0021] Polypropylene glycol dispersant 0.1-0.2 parts;

[0022] 0.1-0.2 parts of organosilicon quaternary ammonium salt mildew preventive and fungicide.

[0023] Specifically, the preparation method of the modified diatomaceous earth includes:

[0024] (1) Dry 1250 mesh diatomaceous earth at 120°C for 4 hours;

[0025] (2) reacting the dried diatomaceous earth with 3-4 parts by weight of silane coupling agent KH-550 at 80° C. with mechanical stirring for 2 hours;

[0026] (3) The reaction product was vacuum-dried at 110° C. for 3 hours, crushed and sieved to obtain the modified diatomaceous earth.

[0027] Specifically, the preparation method of the surface-treated kaolin includes:

[0028] (1) 800 mesh kaolin was dispersed in deionized water with a solid content of 30 wt%;

[0029] (2) adding 2-3 parts by weight of sodium hexametaphosphate to the dispersion and stirring evenly;

[0030] (3) Adjust the pH to 8-9, heat to 70°C and stir for 1 hour;

[0031] (4) Filtering, drying the filter cake at 105° C. for 4 hours, crushing and sieving to obtain the surface-treated kaolin.

[0032] Specifically, the preparation method of the modified talc powder includes:

[0033] (1) Place 1000 mesh talc powder in an ultrasonic disperser;

[0034] (2) adding 2-3 parts by weight of stearic acid and ultrasonically treating for 30 minutes;

[0035] (3) stirring the mixture at 90°C for 2 hours;

[0036] (4) Filtering, drying the filter cake at 100° C. for 3 hours, crushing and sieving to obtain the modified talc powder.

[0037] Specifically, the solid content of the styrene acrylic emulsion and the acrylic ester emulsion are both 50%, and the viscosity is 400-800 cps / 25°C.

[0038] A method for preparing the multifunctional water-based interior wall coating comprises the following steps:

[0039] (1) Pre-dispersion of filler: the modified diatomaceous earth, the surface-treated kaolin, and the modified talc are mixed, 0.5-1% of the polypropylene glycol dispersant accounting for the total weight of the filler is added, and high-speed dispersion is carried out at below 30° C. for 15-20 minutes to obtain a filler dispersion;

[0040] (2) pre-mixing the emulsion: mixing the styrene acrylic emulsion and the acrylic ester emulsion at a rotation speed of 200-300 rpm to obtain an emulsion mixture;

[0041] (3) Main body preparation:

[0042] a) adding the filler dispersion to the emulsion mixture and stirring uniformly;

[0043] b) adding the dipropylene glycol monobutyl ether and the glycerol butyl ether acetate in sequence and stirring for 10 minutes;

[0044] c) adding the organosilicon-modified polyacrylate and the fluorocarbon surfactant and stirring for 15 minutes;

[0045] d) adding the defoamer, the wetting agent BYK-331, the thickener ASE-60 and the organosilicon quaternary ammonium salt mildew and fungicide in sequence.

[0046] Specifically, the temperature of the main body preparation in step (3) is controlled below 35°C.

[0047] Specifically, the main body is ground after preparation, and the grinding fineness is controlled at 25-30 μm.

[0048] Specifically, after the main body is prepared, a final inspection is performed to control the product viscosity to be 3000-5000 mPa·s.

[0049] Specifically, the addition temperature of the thickener ASE-60 is controlled at 20-25° C., the stirring speed is 300-500 rpm, and the stirring time is 20-30 minutes.

[0050] Compared with the prior art, the multifunctional water-based paint for interior walls and the preparation method thereof of the present invention can achieve the following beneficial effects:

[0051] First, an interpenetrating network structure based on a styrene acrylic / acrylate two-component emulsion was designed. The benzene ring structure of the styrene acrylic emulsion provides excellent weather resistance and mechanical strength, while the carboxyl and ester groups of the acrylate impart good flexibility and adhesion to the system. Through a precisely controlled premixing process, the two emulsions form a synergistic interpenetrating network structure.

[0052] Secondly, a silane coupling agent is innovatively used to modify the diatomite surface. The siloxy groups of the silane coupling agent undergo a condensation reaction with the hydroxyl groups on the diatomite surface, while its organic groups form chemical bonds with the emulsion matrix, achieving strong compatibility between the filler and the matrix. Furthermore, the modified diatomite retains its unique porous structure, which not only provides numerous formaldehyde adsorption sites but also forms microchannels that regulate humidity and allow for ventilation.

[0053] Thirdly, through the innovative combination of silicone-modified polyacrylate and fluorocarbon surfactant, a dual hydrophobic protection network is constructed. The silicone groups form a stable chemical bond with the substrate through Si-O bonds, while the fluorocarbon segments form a regularly arranged low surface energy layer on the surface. The synergistic effect of the two achieves a long-lasting hydrophobic and antifouling effect.

[0054] Finally, a precisely controlled step-by-step feeding process and temperature control system ensures the uniform dispersion and full effectiveness of each functional component. In particular, the temperature and shear force control during the filler pre-dispersion stage effectively prevents agglomeration.

[0055] The technical solution of this invention not only solves the problems existing in the prior art but also achieves several unexpected technical benefits: First, the coating exhibits ultra-long-lasting self-cleaning properties, maintaining excellent hydrophobicity even after 3,000 hours of accelerated aging. Second, while maintaining high hydrophobicity, the coating also exhibits good air permeability and intelligent humidity control, thanks to the multi-level pore structure created by the modified filler. Furthermore, the coating exhibits excellent antibacterial properties, a result of the synergistic effect of the hydrophobic surface's physical protection and chemical sterilization.

[0056] In summary, the present invention has developed a new type of interior wall paint with long-lasting self-cleaning, air purification and humidity control functions through multiple technological innovations and synergistic effects, providing a new solution for indoor environmental health. DETAILED DESCRIPTION

[0057] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0058] Example 1 A multifunctional water-based interior wall paint and its preparation method

[0059] The multifunctional water-based paint for interior walls of this embodiment includes the following components in parts by weight: 32 parts of styrene-acrylic emulsion, 16 parts of acrylate emulsion, 22 parts of modified diatomaceous earth, 12 parts of surface-treated kaolin, 6 parts of modified talc, 1.2 parts of dipropylene glycol monobutyl ether, 1.3 parts of propylene glycol butyl ether acetate, 0.6 parts of organosilicon-modified polyacrylate, 0.7 parts of fluorocarbon surfactant, 0.3 parts of defoaming agent, 0.4 parts of wetting agent BYK-331, 0.8 parts of thickener ASE-60, 0.15 parts of polypropylene glycol dispersant, and 0.15 parts of organosilicon quaternary ammonium salt antifungal and fungicide, such as SQ-5700 of Hunan Lijie Biological Group Co., Ltd.

[0060] The styrene acrylic emulsion and the acrylic emulsion both have a solids content of 50% and a viscosity of 500 cps / 25°C. Preferably, the styrene acrylic emulsion provides excellent weather resistance and hardness, while the acrylic emulsion imparts good flexibility and adhesion to the coating. The two form an interpenetrating network structure, significantly improving the overall performance of the coating.

[0061] The preparation methods of the modified fillers in this embodiment are as follows:

[0062] First, the modified diatomaceous earth was prepared by drying 1250 mesh diatomaceous earth at 120°C for 4 hours. The dried diatomaceous earth was then reacted with 3.5 parts by weight of the silane coupling agent KH-550 at 80°C for 2 hours with mechanical stirring. Finally, the reaction product was vacuum-dried at 110°C for 3 hours, crushed, and sieved to obtain the modified diatomaceous earth. The modification with the silane coupling agent significantly improved the compatibility of the diatomaceous earth with the resin matrix while maintaining its unique porous structure, which is beneficial for enhancing the coating's formaldehyde adsorption performance.

[0063] Next, surface-treated kaolin was prepared by dispersing 800-mesh kaolin in deionized water to a solid content of 30 wt%. 2.5 parts by weight of sodium hexametaphosphate was added to the dispersion and stirred evenly. The pH was adjusted to 8.5, the mixture was heated to 70°C and stirred for one hour. After filtering, the resulting filter cake was dried at 105°C for four hours, crushed, and sieved to obtain the surface-treated kaolin. The sodium hexametaphosphate surface treatment significantly improved the dispersibility of the kaolin and enhanced its compatibility with the emulsion system.

[0064] Next, the modified talc was prepared by placing 1000-mesh talc in an ultrasonic disperser; adding 2.5 parts by weight of stearic acid and ultrasonically treating for 30 minutes; stirring the mixture at 90°C for 2 hours; filtering the mixture, drying the filter cake at 100°C for 3 hours, and then pulverizing and sieving to obtain the modified talc. Stearic acid modification not only improves the hydrophobicity of the talc but also enhances its dispersion stability in the system.

[0065] The preparation method of the multifunctional water-based paint for interior walls comprises the following steps:

[0066] (1) Filler pre-dispersion: The prepared modified diatomaceous earth, surface-treated kaolin, and modified talc are mixed, and a polypropylene glycol dispersant (0.8% by weight of the total filler) is added. The mixture is dispersed at high speed at 28°C for 18 minutes to obtain a filler dispersion. In this step, the dispersion temperature and time are precisely controlled to ensure that the filler is fully dispersed, laying the foundation for subsequent processes.

[0067] (2) Emulsion premixing: Mix the styrene acrylic emulsion and the acrylic emulsion at 250 rpm for 15 minutes to obtain an emulsion mixture. In this step, the gentle stirring conditions are conducive to the full compatibility of the two emulsions and the formation of a stable interpenetrating network structure;

[0068] (3) Main body preparation:

[0069] a) slowly adding the filler dispersion to the emulsion mixture at a stirring speed of 400 rpm for 15 minutes;

[0070] b) adding dipropylene glycol monobutyl ether and glycerol butyl ether acetate in sequence, stirring at 350 rpm for 10 minutes;

[0071] c) adding organosilicon-modified polyacrylate and fluorocarbon surfactant, stirring at 300 rpm for 15 minutes;

[0072] d) Add defoamer, wetting agent BYK-331, thickener ASE-60 and silicone quaternary ammonium salt mildew and fungicide in sequence, stirring at 400 rpm for 25 minutes.

[0073] Throughout the entire main preparation process, the temperature was strictly controlled below 32°C. Grinding was then performed, with a fineness of 28 μm. Finally, a final inspection revealed a viscosity of 3500 mPa·s.

[0074] Example 2 A multifunctional water-based interior wall paint and its preparation method

[0075] The multifunctional water-based interior wall paint of this embodiment includes the following components in parts by weight: 30 parts of styrene-acrylic emulsion, 20 parts of acrylate emulsion, 25 parts of modified diatomaceous earth, 10 parts of surface-treated kaolin, 8 parts of modified talc, 1.5 parts of dipropylene glycol monobutyl ether, 1.5 parts of propylene glycol butyl ether acetate, 1 part of organosilicon-modified polyacrylate, 1 part of fluorocarbon surfactant, 0.5 part of defoamer, 0.6 part of wetting agent BYK-331, 1.5 parts of thickener ASE-60, 0.2 part of polypropylene glycol dispersant, and 0.2 part of organosilicon quaternary ammonium salt mildew and fungicide.

[0076] The solid content of the styrene acrylic emulsion and the acrylic ester emulsion are both 50% and the viscosity is 800 cps / 25° C. In this embodiment, a higher viscosity emulsion system is used to provide better construction performance and suspension stability.

[0077] The preparation methods of the modified fillers in this embodiment are as follows:

[0078] First, modified diatomite was prepared by drying 1250 mesh diatomite at 120°C for 4 hours. The dried diatomite was then reacted with 4 parts by weight of a silane coupling agent, KH-550, at 80°C for 2 hours under mechanical stirring. Finally, the reaction product was vacuum-dried at 110°C for 3 hours, crushed, and sieved to obtain the modified diatomite. In this example, the amount of coupling agent was increased to further enhance the bonding strength between the filler and the matrix.

[0079] Secondly, preparation of surface-treated kaolin: 800 mesh kaolin was dispersed in deionized water, and the solid content was controlled to 30 wt%; 3 parts by weight of sodium hexametaphosphate was added to the dispersion and stirred evenly; the pH was adjusted to 9, the temperature was raised to 70°C and stirred for 1 hour; after filtering, the filter cake was dried at 105°C for 4 hours, crushed and sieved to obtain surface-treated kaolin.

[0080] Again, the preparation of modified talc powder: 1000 mesh talc powder is placed in an ultrasonic disperser; 3 parts by weight of stearic acid is added and ultrasonically treated for 30 minutes; the mixture is stirred and reacted at 90°C for 2 hours; after filtering, the filter cake is dried at 100°C for 3 hours, crushed and sieved to obtain modified talc powder.

[0081] The preparation method of the multifunctional water-based paint for interior walls comprises the following steps:

[0082] (1) Pre-dispersion of filler: The prepared modified diatomaceous earth, surface-treated kaolin and modified talc were mixed, and a polypropylene glycol dispersant accounting for 1% of the total weight of the filler was added, and the mixture was dispersed at high speed at 30° C. for 20 minutes to obtain a filler dispersion;

[0083] (2) Emulsion premixing: Styrene acrylic emulsion and acrylic ester emulsion were mixed at 300 rpm for 20 minutes to obtain an emulsion mixture;

[0084] (3) Main body preparation:

[0085] a) slowly adding the filler dispersion to the emulsion mixture at a stirring speed of 450 rpm for 20 minutes;

[0086] b) adding dipropylene glycol monobutyl ether and glycerol butyl ether acetate in sequence, stirring at 400 rpm for 15 minutes;

[0087] c) adding organosilicon-modified polyacrylate and fluorocarbon surfactant, stirring at 350 rpm for 20 minutes;

[0088] d) Add defoamer, wetting agent BYK-331, thickener ASE-60 and organosilicon quaternary ammonium salt mildew and fungicide in sequence, stirring at 450 rpm for 30 minutes.

[0089] Throughout the entire main preparation process, the temperature was strictly controlled below 35°C. Grinding was then performed, with a fineness of 25 μm. Finally, a final inspection revealed a product viscosity of 5000 mPa·s.

[0090] Example 3 A multifunctional water-based interior wall paint and its preparation method

[0091] The multifunctional water-based interior wall paint of this embodiment includes the following components in parts by weight: 35 parts of styrene-acrylic emulsion, 15 parts of acrylate emulsion, 20 parts of modified diatomaceous earth, 15 parts of surface-treated kaolin, 5 parts of modified talc, 1 part of dipropylene glycol monobutyl ether, 1 part of propylene glycol butyl ether acetate, 0.5 part of organosilicon-modified polyacrylate, 0.5 part of fluorocarbon surfactant, 0.2 part of defoamer, 0.3 part of wetting agent BYK-331, 0.5 part of thickener ASE-60, 0.1 part of polypropylene glycol dispersant, and 0.1 part of organosilicon quaternary ammonium salt mildew and fungicide.

[0092] The solid content of the styrene acrylic emulsion and the acrylic ester emulsion are both 50%, and the viscosity is 400 cps / 25° C. In this embodiment, the ratio of the two emulsions is adjusted to increase the proportion of the styrene acrylic emulsion to improve the weather resistance of the coating.

[0093] The preparation methods of the modified fillers in this embodiment are as follows:

[0094] First, modified diatomaceous earth was prepared by drying 1250 mesh diatomaceous earth at 120° C. for 4 hours; then, the dried diatomaceous earth and 3 parts by weight of silane coupling agent KH-550 were reacted at 80° C. for 2 hours with mechanical stirring; finally, the reaction product was vacuum dried at 110° C. for 3 hours, crushed and sieved to obtain modified diatomaceous earth.

[0095] Secondly, preparation of surface-treated kaolin: 800 mesh kaolin was dispersed in deionized water, and the solid content was controlled to 30 wt%; 2 parts by weight of sodium hexametaphosphate was added to the dispersion and stirred evenly; the pH was adjusted to 8, the temperature was raised to 70°C and stirred for 1 hour; after filtering, the filter cake was dried at 105°C for 4 hours, crushed and sieved to obtain surface-treated kaolin.

[0096] Again, the preparation of modified talc powder: 1000 mesh talc powder is placed in an ultrasonic disperser; 2 parts by weight of stearic acid is added and ultrasonically treated for 30 minutes; the mixture is stirred and reacted at 90°C for 2 hours; after filtering, the filter cake is dried at 100°C for 3 hours, crushed and sieved to obtain modified talc powder.

[0097] The preparation method of the multifunctional water-based paint for interior walls comprises the following steps:

[0098] (1) Pre-dispersion of filler: The prepared modified diatomaceous earth, surface-treated kaolin and modified talc were mixed, and a polypropylene glycol dispersant accounting for 0.5% of the total weight of the filler was added, and the mixture was dispersed at high speed at 25° C. for 15 minutes to obtain a filler dispersion;

[0099] (2) Emulsion premixing: Styrene acrylic emulsion and acrylic ester emulsion were mixed at a speed of 200 rpm for 10 minutes to obtain an emulsion mixture;

[0100] (3) Main body preparation:

[0101] a) slowly adding the filler dispersion to the emulsion mixture at a stirring speed of 350 rpm for 10 minutes;

[0102] b) adding dipropylene glycol monobutyl ether and glycerol butyl ether acetate in sequence, stirring at 300 rpm for 8 minutes;

[0103] c) adding organosilicon-modified polyacrylate and fluorocarbon surfactant, stirring at 250 rpm for 12 minutes;

[0104] d) Add defoamer, wetting agent BYK-331, thickener ASE-60 and silicone quaternary ammonium salt mildew and fungicide in sequence, stirring at 350 rpm for 20 minutes.

[0105] Throughout the entire main preparation process, the temperature was strictly controlled below 30°C. Grinding was then performed, with a fineness of 30 μm. Finally, a final inspection revealed a product viscosity of 3000 mPa·s.

[0106] Example 4 A multifunctional water-based interior wall paint and its preparation method

[0107] The multifunctional water-based paint for interior walls of this embodiment includes the following components in parts by weight: 33 parts of styrene-acrylic emulsion, 17 parts of acrylate emulsion, 23 parts of modified diatomaceous earth, 13 parts of surface-treated kaolin, 7 parts of modified talc, 1.3 parts of dipropylene glycol monobutyl ether, 1.4 parts of propylene glycol butyl ether acetate, 0.8 part of organosilicon-modified polyacrylate, 0.8 part of fluorocarbon surfactant, 0.4 part of defoamer, 0.5 part of wetting agent BYK-331, 1 part of thickener ASE-60, 0.18 part of polypropylene glycol dispersant, and 0.18 part of organosilicon quaternary ammonium salt mildew and fungicide.

[0108] The solid content of the styrene acrylic emulsion and the acrylic ester emulsion are both 50% and the viscosity is 600 cps / 25° C. This embodiment adopts an emulsion system with a medium viscosity to achieve a good balance between construction performance and coating performance.

[0109] The preparation methods of the modified fillers in this embodiment are as follows:

[0110] First, modified diatomaceous earth was prepared by drying 1250 mesh diatomaceous earth at 120° C. for 4 hours; then, the dried diatomaceous earth and 3.8 parts by weight of silane coupling agent KH-550 were reacted at 80° C. for 2 hours with mechanical stirring; finally, the reaction product was vacuum dried at 110° C. for 3 hours, crushed and sieved to obtain modified diatomaceous earth.

[0111] Secondly, preparation of surface-treated kaolin: 800 mesh kaolin was dispersed in deionized water, and the solid content was controlled to 30 wt%; 2.8 parts by weight of sodium hexametaphosphate was added to the dispersion and stirred evenly; the pH was adjusted to 8.8, the temperature was raised to 70°C and stirred for 1 hour; after filtering, the filter cake was dried at 105°C for 4 hours, crushed and sieved to obtain surface-treated kaolin.

[0112] Again, the preparation of modified talc powder: 1000 mesh talc powder is placed in an ultrasonic disperser; 2.8 parts by weight of stearic acid is added and ultrasonically treated for 30 minutes; the mixture is stirred and reacted at 90°C for 2 hours; after filtering, the filter cake is dried at 100°C for 3 hours, crushed and sieved to obtain modified talc powder.

[0113] The preparation method of the multifunctional water-based paint for interior walls comprises the following steps:

[0114] (1) Pre-dispersion of filler: The prepared modified diatomaceous earth, surface-treated kaolin, and modified talc were mixed, and a polypropylene glycol dispersant accounting for 0.8% of the total weight of the filler was added, and the mixture was dispersed at high speed at 27° C. for 17 minutes to obtain a filler dispersion;

[0115] (2) Emulsion premixing: Styrene acrylic emulsion and acrylic ester emulsion were mixed at a rotation speed of 275 rpm for 18 minutes to obtain an emulsion mixture;

[0116] (3) Main body preparation:

[0117] a) slowly adding the filler dispersion to the emulsion mixture at a stirring speed of 425 rpm for 18 minutes;

[0118] b) adding dipropylene glycol monobutyl ether and glycerol butyl ether acetate in sequence, stirring at 375 rpm for 12 minutes;

[0119] c) adding organosilicon-modified polyacrylate and fluorocarbon surfactant, stirring at 325 rpm for 18 minutes;

[0120] d) Defoamer, wetting agent BYK-331, thickener ASE-60, and silicone quaternary ammonium salt mildew and fungicide were added in sequence, with stirring at 425 rpm for 28 minutes.

[0121] Throughout the entire main preparation process, the temperature was strictly controlled below 33°C. Grinding was then performed, with a fineness of 27 μm. Finally, a final inspection revealed a product viscosity of 4000 mPa·s.

[0122] Comparative Example 1 A multifunctional water-based interior wall coating and its preparation method

[0123] This comparative example, intended to verify the necessity of filler modification, employed the same component proportions as in Example 1, but used unmodified raw fillers. This multifunctional water-based interior wall coating comprised the following components by weight: 32 parts styrene-acrylic emulsion, 16 parts acrylate emulsion, 22 parts unmodified diatomaceous earth, 12 parts unmodified kaolin, and 6 parts unmodified talc. The amounts of the other components were identical to those in Example 1.

[0124] The solid content and viscosity parameters of the styrene acrylic emulsion and the acrylic ester emulsion are the same as those in Example 1. It is worth noting that since the filler is not modified, its surface activity is poor and its compatibility with the emulsion system is significantly reduced.

[0125] The preparation method of the multifunctional water-based paint for interior walls comprises the following steps:

[0126] (1) Filler pre-dispersion: Unmodified diatomaceous earth, kaolin, and talc were directly mixed, with other conditions being the same as in Example 1;

[0127] (2) Emulsion premixing: process parameters are the same as those in Example 1;

[0128] (3) Main body preparation: The process parameters are the same as those in Example 1.

[0129] Comparative studies with Example 1 show that due to the lack of a filler modification step, the product of this comparative example has the following significant deficiencies: First, the filler easily agglomerates in the system, resulting in poor dispersion stability and a sedimentation value 2.5 times that of Example 1. Second, because the filler surface has not been activated, its interfacial bonding with the emulsion matrix is ​​weak, resulting in a more than 30% decrease in coating adhesion. Third, the adsorption active sites of the unmodified diatomaceous earth are significantly reduced, resulting in an approximately 40% decrease in formaldehyde adsorption rate. These results fully demonstrate the necessity and creativity of the filler modification process of the present invention.

[0130] Comparative Example 2 A multifunctional water-based interior wall paint and its preparation method

[0131] This comparative example verifies the criticality of the emulsion system ratio by adjusting the emulsion ratio. The multifunctional water-based interior wall paint comprises the following components by weight: 20 parts styrene acrylic emulsion and 30 parts acrylate emulsion (for comparison with Example 2). The amounts of other components are exactly the same as in Example 2.

[0132] In this comparative example, the original optimal ratio relationship was broken by reducing the proportion of styrene acrylic emulsion and increasing the proportion of acrylic ester emulsion. This change directly affected the formation of the interpenetrating network structure of the emulsion.

[0133] The preparation method of the multifunctional water-based interior wall paint is the same as that of Example 2. This design ensures the consistency of process parameters and can accurately evaluate the impact of changes in emulsion ratios.

[0134] Comparative studies revealed significant degradation in product performance due to the change in emulsion ratio. First, the coating's weatherability significantly decreased, with the yellowing index increasing 2.5-fold after 240 hours of QUV accelerated aging. Second, due to insufficient styrene-acrylic emulsion content, the coating's surface hardness decreased by 25%, with the pencil hardness dropping from 3H to H. Third, scrub resistance significantly decreased, with noticeable wear occurring after 1,000 standard scrubs. These results demonstrate the specific technical effectiveness of the emulsion ratio selected in this invention.

[0135] Comparative Example 3: A multifunctional water-based interior wall paint and its preparation method

[0136] This comparative example verifies the critical significance of the amount of filler modifier used. The component proportions of this multifunctional interior wall water-based paint are the same as those in Example 3, except that during the filler modification process, the amount of silane coupling agent is reduced to 1.5 parts by weight, the amount of sodium hexametaphosphate is reduced to 1 part by weight, and the amount of stearic acid is reduced to 1 part by weight.

[0137] Among them, the filler modification method is as follows:

[0138] The preparation process parameters for the modified diatomite were the same as those in Example 3, except that the amount of silane coupling agent KH-550 was reduced to 1.5 parts by weight; the other filler modification processes were similarly adjusted. This change resulted in insufficient filler surface modification and unsatisfactory modification results.

[0139] Performance testing revealed that, first, insufficient surface modification of the filler reduced its compatibility with the substrate. Second, the coating's water resistance significantly decreased, with a 24-hour water absorption rate increasing by 80%. Third, the coating's overall mechanical properties declined, with impact strength decreasing by 40%. This clearly demonstrates that the modifier dosage in this invention has a necessary critical value.

[0140] Comparative Example 4: A multifunctional water-based interior wall coating and its preparation method

[0141] This comparative example focuses on verifying the importance of preparation process parameters. The same formulation as Example 4 was used, but key process parameters were changed. The details are as follows:

[0142] The filler pre-dispersion temperature was increased to 45°C and the time was shortened to 8 minutes; the emulsion pre-mixing speed was increased to 500 rpm; and the temperature of the main preparation process was controlled at 45°C. These parameter changes exceeded the optimal range of the present invention.

[0143] The experimental results show that: first, the higher pre-dispersion temperature leads to abnormal viscosity of the system and local gelation; second, the too fast stirring speed causes a large number of bubbles to be introduced into the system, affecting the film-forming quality; third, the higher preparation temperature accelerates the pre-cross-linking of the emulsion, resulting in poor storage stability.

[0144] Comparative Example 5: A multifunctional water-based interior wall paint and its preparation method

[0145] This comparative example verifies the synergistic effect of the auxiliary agent combination. Based on the formula of Example 1, the organosilicon-modified polyacrylate is deleted and only the fluorocarbon surfactant is used, and the amount of the fluorocarbon surfactant is increased to 1.5 parts.

[0146] The experimental results show that although the amount of fluorocarbon surfactant was increased alone, the product performance still showed a significant decline due to the lack of synergistic effect with silicone-modified polyacrylate: first, the hydrophobicity of the coating was unstable, and the contact angle decreased significantly over time; second, the coating's anti-fouling performance decreased, especially the protection against oil stains was reduced by 50%; third, the durability of the coating was also reduced accordingly.

[0147] Comparative Example 6: A multifunctional water-based interior wall paint and its preparation method

[0148] This comparative example demonstrates the importance of filler particle size distribution. The formulation of Example 2 was used, but the mesh size of all three fillers was adjusted to 400 mesh. Other components and process parameters remained unchanged.

[0149] The test results show that due to the unreasonable distribution of filler particle size, the following problems arise: first, the specific surface area of ​​the filler is significantly reduced, resulting in a decrease in functional performance; second, the coarse particle filler affects the leveling of the coating and increases the surface roughness; third, the covering power of the coating decreases by 30%, and the coating thickness needs to be increased to achieve the desired covering effect.

[0150] The six comparative examples above demonstrate the novelties and technical effects of the present invention from different perspectives, fully demonstrating the necessity and inventiveness of the various technical features of the present invention. In particular, the synergistic effect of the core technical features, such as the filler modification process, emulsion ratio optimization, and process parameter control, contributes to the technical innovation of the present invention.

[0151] Based on the core innovations and mechanism of action of this invention, the following system performance evaluation scheme was designed:

[0152] Performance testing methods

[0153] 1. Basic coating performance test

[0154] The present invention first prepares test samples according to GB / T9286-1998 standard, applies the coating on standard glass plates and cement plates, controls the coating thickness to be 80±5 μm, and tests after curing for 7 days under standard conditions (23±2° C., relative humidity 50±5%).

[0155] The specific test items and methods are as follows:

[0156] Adhesion testing was performed using the GB / T9286-1998 cross-hatch method, with a rating scale of 0-5. Adhesion between the coating and the substrate was also tested using the ASTM D4541 pull-off method. Test conditions were 23±2°C, 50±5% relative humidity, and a pull-off rate of 2.0 MPa / s.

[0157] The coating hardness was tested using the pencil hardness method according to GB / T6739-2006. A Mitsubishi UNI pencil was used and a pressure of 750g was applied at a 45° angle.

[0158] The scrub resistance was tested in accordance with GB / T9266-2009 using a standard scrubber with a weight of 500 g. The number of scrubs required until the coating showed noticeable wear was recorded.

[0159] 2. Functional performance testing

[0160] The hydrophobic performance test adopted the JG / T368-2012 contact angle test method, using the German DataPhysics OCA20 contact angle tester, the test droplet volume was 5μL, and the static contact angle and rolling angle were tested at 23±2℃.

[0161] The formaldehyde adsorption performance was tested using the closed box method according to GB / T18883-2002, with an area of ​​1m 2 The coated sample was placed in a 60L sealed box and injected with an initial concentration of 1.0 mg / m 3 The residual concentration of formaldehyde is tested at 23±2℃ after 24 hours.

[0162] 3. Microstructure Characterization

[0163] The cross-sectional morphology of the coating was observed using a FEI Quanta 250 field emission scanning electron microscope at an accelerating voltage of 15 kV. The sample was fractured in liquid nitrogen and then gold-sprayed on the surface.

[0164] The crystal structure of the filler was analyzed by a Bruker D8 Advance X-ray diffractometer using CuKα radiation with a scanning range of 5-80° 2θ and a scanning speed of 2° / min.

[0165] Table 1 Test results of basic coating properties

[0166]

[0167] Table 2 Coating functional performance test results

[0168]

[0169]

[0170] The test results are analyzed as follows:

[0171] 1. Basic performance advantages

[0172] The test results of Examples 1-4 demonstrated excellent overall performance: adhesion reached Level 1, with adhesion strength ranging from 2.2-2.5 MPa; pencil hardness reached 3H-4H; and scrub resistance exceeded 2000 cycles. Example 2 performed particularly well, primarily due to the optimized emulsion ratio and filler modification process. In contrast, Comparative Examples 1-6 showed significant declines in all performance indicators. In particular, in Comparative Example 1, due to the unmodified filler, the adhesion strength was only 1.3 MPa.

[0173] 2. Breakthrough in functional performance

[0174] In terms of hydrophobicity, Examples 1-4 all achieved static contact angles exceeding 150° and rolling angles less than 5°, demonstrating excellent self-cleaning properties. In particular, Example 2 achieved a contact angle of 156°, attributed to the synergistic effect of the silicone-modified polyacrylate and the fluorocarbon surfactant.

[0175] Formaldehyde adsorption performance tests showed that the 24-hour formaldehyde removal rates of Examples 1-4 all exceeded 90%, with Example 3 reaching 95.8%. This was mainly attributed to the synergistic effect of the porous structure and surface active sites of the modified diatomaceous earth.

[0176] 3. Analysis of microscopic mechanisms

[0177] SEM observation results show that the cross section of the coating of Example 2 exhibits a typical interpenetrating network structure, with the modified filler and the resin matrix tightly bonded at the interface, with no obvious interface delamination. However, the cross section of Comparative Example 1 exhibits obvious filler agglomeration and interface delamination.

[0178] XRD analysis further confirmed the success of filler modification. A characteristic peak appeared at 2θ=23.5° in the modified diatomaceous earth, indicating that the silane coupling agent was successfully grafted onto the filler surface.

[0179] In addition, the present invention also has the following unexpected technical effects:

[0180] 1. Ultra-long-lasting self-cleaning performance

[0181] After 3000 hours of natural aging testing, the coating of Example 2 maintained a contact angle of over 150°, significantly exceeding the state-of-the-art. This durable hydrophobicity stems from the dual hydrophobic network structure formed by the silicone-modified polyacrylate and the fluorocarbon surfactant. Even when the surface layer wears, the underlying layer retains its hydrophobic properties.

[0182] 2. Intelligent humidity control function

[0183] It was unexpectedly found that the coating of the present invention has excellent humidity regulation ability. Under the condition of relative humidity of 75%, the moisture absorption rate is 38g / m 2 When the relative humidity drops to 35%, it can slowly release water. This characteristic is due to the synergistic effect of the multi-level pore structure of modified diatomite and the surface modification groups.

[0184] 3. Antibacterial synergistic effect

[0185] In the antibacterial performance test, it was found that the coating of the present invention had an inhibition rate of more than 99% against Escherichia coli and Staphylococcus aureus. This effect was partly attributed to the physical protective barrier constructed by the hydrophobic surface and the chemical synergistic effect of the organosilicon quaternary ammonium salt antifungal and fungicide.

[0186] From the test data, it can be seen that Example 2 has the best overall performance, which is mainly due to:

[0187] The best emulsion ratio (30 parts styrene acrylic, 20 parts acrylate);

[0188] Optimized filler modification process (4 parts by weight of coupling agent);

[0189] Precisely controlled preparation process parameters;

[0190] Key performance indicator comparison:

[0191] Adhesion strength: The average adhesion strength of the embodiment group is more than 50% higher than that of the comparative example group;

[0192] Scrub resistance: The example groups generally exceeded 2000 times, while the comparative example groups were mostly below 1000 times;

[0193] Hydrophobicity: The contact angles of the example groups all exceeded 150°, while those of the comparative groups were generally lower than 120°;

[0194] Formaldehyde removal rate: The Example groups all exceeded 90%, while the Comparative Example groups were generally below 70%;

[0195] Outstanding durability:

[0196] Storage stability is more than 12 months;

[0197] Excellent aging resistance, performance remains stable after 2000h test;

[0198] Good alkali resistance, no obvious change after 168h immersion;

[0199] These data fully demonstrate the synergistic effect of the various technical features of the present invention, especially the innovation and necessity of core technologies such as modified fillers, emulsion ratio optimization, and process parameter control.

[0200] In summary, a systematic performance evaluation fully demonstrates the significant advantages of this invention in terms of basic and functional properties, particularly the breakthroughs in durability, self-cleaning properties, and air purification. These excellent properties, derived from the synergistic effects of various components and precise process control, constitute the core technological innovation of this invention.

[0201] The foregoing is merely an embodiment of the present invention and is not intended to limit the present invention. It will be apparent to those skilled in the art that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of the present invention.

Claims

1. A multifunctional water-based paint for interior walls, characterized in that: The composition comprises the following components in parts by weight: 30-35 parts of styrene acrylic emulsion; Acrylate emulsion 15-20 parts; 20-25 parts of modified diatomaceous earth; Surface treated kaolin 10-15 parts; 5-8 parts of modified talc; 1-1.5 parts of dipropylene glycol monobutyl ether; 1-1.5 parts of propylene glycol butyl ether acetate; 0.5-1 part of silicone modified polyacrylate; 0.5-1 part of fluorocarbon surfactant; Defoaming agent 0.2-0.5 parts; Wetting agent BYK-331 0.3-0.6 parts; Thickener ASE-60 0.5-1.5 parts; Polypropylene glycol dispersant 0.1-0.2 parts; 0.1-0.2 parts of silicone quaternary ammonium salt mildew preventer and fungicide.

2. The multifunctional water-based paint for interior walls according to claim 1, characterized in that: The preparation method of the modified diatomite comprises: (1) Dry 1250 mesh diatomaceous earth at 120°C for 4 hours; (2) reacting the dried diatomaceous earth with 3-4 parts by weight of silane coupling agent KH-550 at 80° C. with mechanical stirring for 2 hours; (3) The reaction product was vacuum dried at 110° C. for 3 hours, crushed and sieved to obtain the modified diatomaceous earth.

3. The multifunctional water-based paint for interior walls according to claim 1, characterized in that: The preparation method of the surface-treated kaolin comprises: (1) 800 mesh kaolin was dispersed in deionized water with a solid content of 30 wt%; (2) adding 2-3 parts by weight of sodium hexametaphosphate to the dispersion and stirring evenly; (3) Adjust the pH to 8-9, raise the temperature to 70°C and stir for 1 hour; (4) filtering, drying the obtained filter cake at 105° C. for 4 hours, crushing and sieving to obtain the surface-treated kaolin.

4. The multifunctional water-based paint for interior walls according to claim 1, characterized in that: The preparation method of the modified talcum powder comprises: (1) Place 1000 mesh talc powder in an ultrasonic disperser; (2) adding 2-3 parts by weight of stearic acid and ultrasonically treating for 30 minutes; (3) stirring the mixture at 90° C. for 2 hours; (4) filtering, drying the filter cake at 100° C. for 3 hours, crushing and sieving to obtain the modified talc powder.

5. The multifunctional water-based paint for interior walls according to claim 1, characterized in that: The solid content of the styrene acrylic emulsion and the acrylic ester emulsion are both 50%, and the viscosity is 400-800 cps / 25°C.

6. A method for preparing the multifunctional water-based interior wall paint according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) pre-dispersing the filler: mixing the modified diatomaceous earth, the surface-treated kaolin and the modified talc, adding 0.5-1% of the polypropylene glycol dispersant accounting for the total weight of the filler, and dispersing at a high speed below 30° C. for 15-20 minutes to obtain a filler dispersion; (2) premixing of emulsions: mixing the styrene acrylic emulsion and the acrylic ester emulsion at a rotation speed of 200-300 rpm to obtain an emulsion mixture; (3) Main body preparation: a) adding the filler dispersion into the emulsion mixture and stirring evenly; b) adding the dipropylene glycol monobutyl ether and the propylene glycol butyl ether acetate in sequence, and stirring for 10 minutes; c) adding the organosilicon-modified polyacrylate and the fluorocarbon surfactant, and stirring for 15 minutes; d) adding the defoamer, the wetting agent BYK-331, the thickener ASE-60 and the organosilicon quaternary ammonium salt mildew and fungicide in sequence.

7. The method according to claim 6, characterized in that The temperature of the main body preparation in step (3) is controlled below 35°C.

8. The method according to claim 6, characterized in that The main body is ground after preparation, and the grinding fineness is controlled at 25-30 μm.

9. The method according to claim 6, characterized in that After the main body is prepared, a final inspection is performed to control the product viscosity to be 3000-5000 mPa·s.

10. The method according to claim 6, characterized in that The thickener ASE-60 is added at a temperature of 20-25° C., a stirring speed of 300-500 rpm, and a stirring time of 20-30 minutes.

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