High-weather-resistant water-based modified acrylate paint and preparation process thereof

Abstract

The application belongs to the technical field of paint, and provides high-weather-resistant water-based modified acrylate paint and a preparation process thereof.The paint comprises the following raw materials according to weight parts: 25 parts of organic silicon modified acrylate copolymer emulsion, 25 parts of silica sol, 29-32 parts of multi-level hollow ceramic micropearls, 5 parts of alumina whisker, 5 parts of aluminum silicate short fiber, 19-21 parts of nano composite slurry, 11-13 parts of fumed silica aerogel powder slurry, 1.5 parts of dispersing agent, 0.5 parts of defoaming agent, 0.3 parts of wetting agent and 20 parts of deionized water.The obtained paint can make the temperature of the base material not higher than 200 DEG C within at least 30 minutes at 1300 DEG C when the coating thickness is less than 1 mm, and has excellent heat insulation performance; meanwhile, the obtained paint has the advantages of not easy to delaminate, good temperature and humidity stability and good liquid resistance, and has good market application prospect.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to a high weather-resistant water-based modified acrylic coating and its preparation process. Background Technology

[0002] Wood, as a renewable, low-carbon, and environmentally friendly natural building material, has irreplaceable value in fields such as the preservation of ancient buildings, modern timber-framed buildings, and specialized industrial warehousing. With the development of modern industrial technology, wood coatings have gradually evolved from their early simple decorative and preservative functions into composite surface engineering technologies that integrate aesthetic expression, environmental tolerance, and functionality. However, despite significant progress in environmental friendliness (such as water-based and UV-cured coatings), construction efficiency, and general weather resistance, performance bottlenecks in extreme high-temperature environments remain prominent. For example, they cannot withstand prolonged use in jet combustion (temperatures often exceeding 1300℃), severely limiting their application in environments with high temperatures or fire risks. While some coating materials can operate in environments exceeding 1000 degrees Celsius, either the coating thickness is typically large, generally used in products where aesthetics are not a primary concern, or the insulation time is short, failing to provide sufficient time for fire suppression or escape.

[0003] Currently, the mainstream wood coating systems, whether solvent-based polyurethane or emerging water-based or UV-cured materials, typically have a thermal stability limit of no more than 400℃. Once exposed to extreme high temperatures above 1300℃, the organic framework will instantly undergo severe thermal oxidation degradation, carbonization, or even combustion, causing the coating to completely lose its structural integrity and protective function, thus failing to achieve effective heat insulation.

[0004] In summary, there is currently a lack of coatings that can provide long-term thermal insulation in ultra-high temperature (>1300℃) environments, ensuring that the temperature of the substrate material remains below the ignition point of wood for extended periods. Therefore, developing a new type of functional coating that can operate stably at temperatures above 1300℃ for extended periods while meeting other performance requirements of general wood coatings is of significant scientific importance and industrialization value. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to develop a coating that exhibits excellent thermal insulation performance under prolonged extremely high temperatures (above 1300℃), and that also possesses characteristics such as resistance to delamination, good temperature and humidity stability, and good liquid resistance. To achieve the aforementioned objectives, the present invention provides the following technical solution: A highly weather-resistant water-based modified acrylic coating, wherein the coating comprises the following raw materials in parts by weight: The composition includes: 25 parts of organosilicon-modified acrylate copolymer emulsion, 25 parts of silica sol, 29-32 parts of multi-graded hollow ceramic microspheres, 5 parts of alumina whiskers, 5 parts of alumina short fibers, 19-21 parts of nanocomposite slurry, 11-13 parts of fumed silica aerogel powder slurry, 1.5 parts of dispersant, 0.5 parts of defoamer, 0.3 parts of wetting agent, and 20 parts of deionized water. The multi-graded hollow ceramic microspheres are obtained by mixing hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm in a weight ratio of 5:3:3. The nanocomposite slurry is prepared by mixing nano titanium dioxide, nano aluminum oxide, hexagonal boron nitride and nano zinc borate in a weight ratio of 1:3 to 5:5:4 to obtain mixed nano powder, which is then dispersed by mixing with deionized water and a dispersant. The fumed silica aerogel slurry is obtained by mixing fumed silica aerogel powder with ethanol and water and stirring until homogeneous.

[0006] Preferably, the dispersant is EFKA-4580; the defoamer is obtained by mixing BYK-028 and BYK-024 in a weight ratio of 2:1.

[0007] Preferably, the wetting agent is TEGO® Wet 270.

[0008] Preferably, the coating comprises the following raw materials in parts by weight: The following ingredients are listed: 25 parts of organosilicon-modified acrylate copolymer emulsion, 25 parts of silica sol, 30 parts of multi-graded hollow ceramic microspheres, 5 parts of alumina whiskers, 5 parts of alumina short fibers, 20 parts of nanocomposite slurry, 12 parts of fumed silica aerogel powder slurry, 1.5 parts of dispersant, 0.5 parts of defoamer, 0.3 parts of wetting agent, and 20 parts of deionized water. The multi-graded hollow ceramic microspheres are obtained by mixing hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm in a weight ratio of 5:3:3. The nanocomposite slurry is prepared by mixing nano-titanium dioxide, nano-alumina, hexagonal boron nitride, and nano-zinc borate in a weight ratio of 1:3:5:4 to obtain mixed nanoparticles, which are then dispersed by mixing with deionized water and a dispersant.

[0009] Preferably, the particle size distribution of nano-titanium dioxide, nano-alumina, and nano-zinc borate is 100~200nm, and the particle size distribution of hexagonal boron nitride is 50~100nm.

[0010] Preferably, the solid content of the organosilicon-modified acrylate copolymer emulsion is 50% w / w, and the SiO2 content in the silica sol is 30% w / w.

[0011] Preferably, the fumed silica aerogel slurry is obtained by the following method: fumed silica aerogel powder, ethanol and water are mixed in a weight ratio of 5:4:1 and stirred at a stirring speed of 400 rpm for 20 min.

[0012] A method for preparing a highly weather-resistant water-based modified acrylic coating, wherein the raw materials for the coating are as described above; the preparation method includes the following steps: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. Under stirring conditions, slowly add fumed silica aerogel powder slurry. After the addition is complete, continue stirring until uniform. Then, under stirring conditions, slowly add nanocomposite slurry. After the addition is complete, continue stirring until uniform. Then, under stirring conditions, slowly add alumina whiskers. After the addition is complete, continue stirring until uniform. (2) Under stirring conditions, slowly add silica sol, and continue stirring until homogeneous after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion, and continue stirring until homogeneous after the addition is complete. (3) Under stirring conditions, slowly add multi-graded hollow ceramic microspheres. After the addition is complete, continue stirring until uniform. Then slowly add aluminum silicate short fibers. After the addition is complete, continue stirring until uniform. (4) Adjust the pH to 8.5 with ammonia water, add the remaining 50% of the formula amount of defoamer and wetting agent under stirring conditions, continue to stir evenly after the addition is complete, filter to remove impurities and let stand to defoam, and the coating is obtained.

[0013] Preferably, the preparation method includes the following steps: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. At a stirring speed of 400 rpm, slowly add fumed silica aerogel powder slurry. After the addition is complete, increase the stirring speed to 800 rpm and stir for 30 min. Then, at a stirring speed of 1500 rpm, slowly add nanocomposite slurry and keep for 30 min after the addition is complete. Then, at a stirring speed of 400 rpm, slowly add alumina whiskers and keep for 30 min after the addition is complete. (2) Add silica sol slowly at a stirring speed of 400 rpm, and keep for 10 min after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion and keep for 15 min after the addition is complete. (3) Keep the stirring speed at 400 rpm, slowly add multi-grade hollow ceramic microspheres, keep for 15 min after the addition is complete, then slowly add aluminum silicate short fibers, keep for 15 min after the addition is complete. (4) Adjust the pH to 8.5 with ammonia water, keep the stirring speed at 400 rpm, add the remaining 50% of the formula amount of defoamer and wetting agent, keep for 30 minutes after the addition is complete, filter with a 100-200 mesh filter, and let stand for 24 hours to defoam before obtaining the coating.

[0014] The aforementioned coatings are used as coating materials for wood-based furniture.

[0015] The beneficial effects of this invention are: The coating obtained by this invention can keep the temperature of the substrate material from exceeding 200°C for at least 30 minutes at 1300°C even when the coating thickness is less than 1 mm, exhibiting excellent heat insulation performance. It is particularly suitable as a coating for substrate materials (such as wood) with an ignition point above 200°C. At the same time, the coating obtained by this invention also has the advantages of being less prone to delamination, having good temperature and humidity stability, and having good liquid resistance, thus having good market application prospects. Detailed Implementation

[0016] The present invention will be specifically described below through embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above-described invention are still within the scope of protection of the present invention.

[0017] Example 1 1. Main raw materials and pretreatment: 1.1 Main Raw Materials: Alumina silicate short fibers (length ≤ 100 micrometers): Lingshou County Chengjiang Mining Processing Plant; Nano titanium dioxide (particle size 100~200nm), nano alumina (particle size 100~200nm), hexagonal boron nitride (h-BN) (particle size 50~100nm), nano zinc borate (particle size 100~200nm): Yangzhou Zhongtianli New Material Co., Ltd.; Fumed silica aerogel powder: Lingshou County Kaiqi Mineral Products Processing Plant; Hollow ceramic microspheres (10 / 30 / 50μm): Shanghai Huijingya Nanomaterials Limited Liability Company; Alumina Whiskers: Suzhou Beike Nanotechnology Co., Ltd.; Organosilicon Modified Acrylate Copolymer Emulsion (50% w / w solid content): Self-made, prepared with reference to the literature "Research on Preparation of Organosilicon Modified Acrylate Copolymer Emulsion by Fine Emulsion Polymerization"; Silica Sol (30% w / w SiO2 content): Shandong Xuxiang Chemical Co., Ltd.; Dispersant EFKA-4580: Guangzhou Haoyi New Material Technology Co., Ltd.; Defoamer BYK-028, Defoamer BYK-024: Qingdao Gudao Technology Co., Ltd.; Wetting Agent TEGO® Wet270: Qingdao Hailaien Chemical Technology Co., Ltd.

[0018] 1.2 Raw material pretreatment Preparation of nanocomposite slurry: Nano-titanium dioxide, nano-alumina, hexagonal boron nitride (h-BN), and nano-zinc borate were prepared in a weight ratio of 1:3:5:4 to obtain mixed nanoparticles; then, the mixed nanoparticles were mixed with a dispersant (20% of the weight of the mixed nanoparticles) and deionized water (3.5 times the weight of the mixed nanoparticles) and dispersed in a high-speed homogenizer (5000 rpm) for 20 min to prepare the nanocomposite slurry.

[0019] Defoamer: Mix defoamer BYK-028 and defoamer BYK-024 at a weight ratio of 2:1 and set aside for later use.

[0020] Multi-graded hollow ceramic microspheres: Hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm are mixed in a weight ratio of 5:3:3 to obtain multi-graded hollow ceramic microspheres.

[0021] Fumed silica aerogel powder slurry: Fumed silica aerogel powder, ethanol and water are mixed in a weight ratio of 5:4:1 and stirred at 400 rpm for 20 min.

[0022] 2. Coating Formulation Design Prepare the following raw materials by weight: 20 parts deionized water, 1.5 parts dispersant EFKA-4580, 0.5 parts defoamer, 0.3 parts wetting agent TEGO® Wet 270, 25 parts organosilicon-modified acrylate copolymer emulsion, 25 parts silica sol, 30 parts multi-graded hollow ceramic microspheres, 5 parts alumina whiskers, 5 parts aluminum silicate short fibers, 20 parts nanocomposite slurry, and 12 parts fumed silica aerogel powder slurry.

[0023] 3. Coating preparation steps: Using the raw materials designed with the aforementioned formula, the following operations are performed: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. At a stirring speed of 400 rpm, slowly add fumed silica aerogel powder slurry. After the addition is complete, increase the stirring speed to 800 rpm and stir for 30 min. Then, at a stirring speed of 1500 rpm, slowly add nanocomposite slurry and keep for 30 min after the addition is complete. Then, at a stirring speed of 400 rpm, slowly add alumina whiskers and keep for 30 min after the addition is complete. (2) Add silica sol slowly at a stirring speed of 400 rpm, and keep for 10 min after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion and keep for 15 min after the addition is complete. (3) Keep the stirring speed at 400 rpm, slowly add multi-grade hollow ceramic microspheres, keep for 15 min after the addition is complete, then slowly add aluminum silicate short fibers, keep for 15 min after the addition is complete. (4) Adjust the pH to 8.5 with ammonia water, keep the stirring speed at 400 rpm, add the remaining 50% of the formula amount of defoamer and wetting agent, keep for 30 minutes after the addition is complete, filter with a 100-200 mesh filter, and let stand for 24 hours to defoam before obtaining the coating.

[0024] Example 2 1. Main raw materials and pretreatment: 1.1 Main Raw Materials: Alumina silicate short fibers (length ≤ 100 micrometers): Lingshou County Chengjiang Mining Processing Plant; Nano titanium dioxide (particle size 100~200nm), nano alumina (particle size 100~200nm), hexagonal boron nitride (h-BN) (particle size 50~100nm), nano zinc borate (particle size 100~200nm): Yangzhou Zhongtianli New Material Co., Ltd.; Fumed silica aerogel powder: Lingshou County Kaiqi Mineral Products Processing Plant; Hollow ceramic microspheres (10 / 30 / 50μm): Shanghai Huijingya Nanomaterials Limited Liability Company; Alumina Whiskers: Suzhou Beike Nanotechnology Co., Ltd.; Organosilicon Modified Acrylate Copolymer Emulsion (50% w / w solid content): Self-made, prepared with reference to the literature "Research on Preparation of Organosilicon Modified Acrylate Copolymer Emulsion by Fine Emulsion Polymerization"; Silica Sol (30% w / w SiO2 content): Shandong Xuxiang Chemical Co., Ltd.; Dispersant EFKA-4580: Guangzhou Haoyi New Material Technology Co., Ltd.; Defoamer BYK-028, Defoamer BYK-024: Qingdao Gudao Technology Co., Ltd.; Wetting Agent TEGO® Wet270: Qingdao Hailaien Chemical Technology Co., Ltd.

[0025] 1.2 Raw material pretreatment Preparation of nanocomposite slurry: Nano-titanium dioxide, nano-alumina, hexagonal boron nitride (h-BN), and nano-zinc borate were prepared in a weight ratio of 1:4:5:4 to obtain mixed nanoparticles; then, the mixed nanoparticles were mixed with a dispersant (20% of the weight of the mixed nanoparticles) and deionized water (3.5 times the weight of the mixed nanoparticles) and dispersed in a high-speed homogenizer (5000 rpm) for 20 min to prepare the nanocomposite slurry.

[0026] Defoamer: Mix defoamer BYK-028 and defoamer BYK-024 at a weight ratio of 2:1 and set aside for later use.

[0027] Multi-graded hollow ceramic microspheres: Hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm are mixed in a weight ratio of 5:3:3 to obtain multi-graded hollow ceramic microspheres.

[0028] Fumed silica aerogel powder slurry: Fumed silica aerogel powder, ethanol and water are mixed in a weight ratio of 5:4:1 and stirred at 400 rpm for 20 min.

[0029] 2. Coating Formulation Design Prepare the following raw materials by weight: 20 parts deionized water, 1.5 parts dispersant EFKA-4580, 0.5 parts defoamer, 0.3 parts wetting agent TEGO® Wet 270, 25 parts organosilicon-modified acrylate copolymer emulsion, 25 parts silica sol, 32 parts multi-graded hollow ceramic microspheres, 5 parts alumina whiskers, 5 parts aluminum silicate short fibers, 21 parts nanocomposite slurry, and 11 parts fumed silica aerogel powder slurry.

[0030] 3. Coating preparation steps: Using the raw materials designed with the aforementioned formula, the following operations are performed: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. At a stirring speed of 400 rpm, slowly add fumed silica aerogel powder slurry. After the addition is complete, increase the stirring speed to 800 rpm and stir for 30 min. Then, at a stirring speed of 1500 rpm, slowly add nanocomposite slurry and keep for 30 min after the addition is complete. Then, at a stirring speed of 400 rpm, slowly add alumina whiskers and keep for 30 min after the addition is complete. (2) Add silica sol slowly at a stirring speed of 400 rpm, and keep for 10 min after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion and keep for 15 min after the addition is complete. (3) Keep the stirring speed at 400 rpm, slowly add multi-grade hollow ceramic microspheres, keep for 15 min after the addition is complete, then slowly add aluminum silicate short fibers, keep for 15 min after the addition is complete. (4) Adjust the pH to 8.5 with ammonia water, keep the stirring speed at 400 rpm, add the remaining 50% of the formula amount of defoamer and wetting agent, keep for 30 minutes after the addition is complete, filter with a 100-200 mesh filter, and let stand for 24 hours to defoam before obtaining the coating.

[0031] Example 3 1. Main raw materials and pretreatment: 1.1 Main Raw Materials: Alumina silicate short fibers (length ≤ 100 micrometers): Lingshou County Chengjiang Mining Processing Plant; Nano titanium dioxide (particle size 100~200nm), nano alumina (particle size 100~200nm), hexagonal boron nitride (h-BN) (particle size 50~100nm), nano zinc borate (particle size 100~200nm): Yangzhou Zhongtianli New Material Co., Ltd.; Fumed silica aerogel powder: Lingshou County Kaiqi Mineral Products Processing Plant; Hollow ceramic microspheres (10 / 30 / 50μm): Shanghai Huijingya Nanomaterials Limited Liability Company; Alumina Whiskers: Suzhou Beike Nanotechnology Co., Ltd.; Organosilicon Modified Acrylate Copolymer Emulsion (50% w / w solid content): Self-made, prepared with reference to the literature "Research on Preparation of Organosilicon Modified Acrylate Copolymer Emulsion by Fine Emulsion Polymerization"; Silica Sol (30% w / w SiO2 content): Shandong Xuxiang Chemical Co., Ltd.; Dispersant EFKA-4580: Guangzhou Haoyi New Material Technology Co., Ltd.; Defoamer BYK-028, Defoamer BYK-024: Qingdao Gudao Technology Co., Ltd.; Wetting Agent TEGO® Wet270: Qingdao Hailaien Chemical Technology Co., Ltd.

[0032] 1.2 Raw material pretreatment Preparation of nanocomposite slurry: Nano-titanium dioxide, nano-alumina, hexagonal boron nitride (h-BN), and nano-zinc borate were prepared in a weight ratio of 1:5:5:4 to obtain mixed nanoparticles; then, the mixed nanoparticles were mixed with a dispersant (20% of the weight of the mixed nanoparticles) and deionized water (3.5 times the weight of the mixed nanoparticles) and dispersed in a high-speed homogenizer (5000 rpm) for 20 min to prepare the nanocomposite slurry.

[0033] Defoamer: Mix defoamer BYK-028 and defoamer BYK-024 at a weight ratio of 2:1 and set aside for later use.

[0034] Multi-graded hollow ceramic microspheres: Hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm are mixed in a weight ratio of 5:3:3 to obtain multi-graded hollow ceramic microspheres.

[0035] Fumed silica aerogel powder slurry: Fumed silica aerogel powder, ethanol and water are mixed in a weight ratio of 5:4:1 and stirred at 400 rpm for 20 min.

[0036] 2. Coating Formulation Design Prepare the following raw materials by weight: 20 parts deionized water, 1.5 parts dispersant EFKA-4580, 0.5 parts defoamer, 0.3 parts wetting agent TEGO® Wet 270, 25 parts organosilicon-modified acrylate copolymer emulsion, 25 parts silica sol, 29 parts multi-graded hollow ceramic microspheres, 5 parts alumina whiskers, 5 parts aluminum silicate short fibers, 19 parts nanocomposite slurry, and 13 parts fumed silica aerogel powder slurry.

[0037] 3. Coating preparation steps: Using the raw materials designed with the aforementioned formula, the following operations are performed: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. At a stirring speed of 400 rpm, slowly add fumed silica aerogel powder slurry. After the addition is complete, increase the stirring speed to 800 rpm and stir for 30 min. Then, at a stirring speed of 1500 rpm, slowly add nanocomposite slurry and keep for 30 min after the addition is complete. Then, at a stirring speed of 400 rpm, slowly add alumina whiskers and keep for 30 min after the addition is complete. (2) Add silica sol slowly at a stirring speed of 400 rpm, and keep for 10 min after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion and keep for 15 min after the addition is complete. (3) Keep the stirring speed at 400 rpm, slowly add multi-grade hollow ceramic microspheres, keep for 15 min after the addition is complete, then slowly add aluminum silicate short fibers, keep for 15 min after the addition is complete. (4) Adjust the pH to 8.5 with ammonia water, keep the stirring speed at 400 rpm, add the remaining 50% of the formula amount of defoamer and wetting agent, keep for 30 minutes after the addition is complete, filter with a 100-200 mesh filter, and let stand for 24 hours to defoam before obtaining the coating.

[0038] Comparative Example 1 Based on Example 1, the silicone-modified acrylate copolymer emulsion was replaced with an acrylate emulsion (Dongguan Delun New Materials Co., Ltd.), while the rest remained the same as in Example 1. Specific details will not be repeated here.

[0039] Comparative Example 2 Based on Example 1, the multi-graded hollow ceramic microspheres were adjusted to have a single particle size of 50 μm, while the rest remained the same as in Example 1. Specific details will not be repeated here.

[0040] Comparative Example 3 Based on Example 1, the mixed nanopowder was adjusted to a single nano-titanium dioxide nanoparticle, and the nanoparticle composite slurry was adjusted to a nanoparticle slurry. The preparation of the nanoparticle slurry was based on the preparation method of the nanoparticle composite slurry in Example 1, but with some adjustments. Specifically, nano-titanium dioxide powder was mixed with a dispersant (15% of the weight of the nano-titanium dioxide powder) and deionized water (3 times the weight of the nano-titanium dioxide powder), and dispersed in a high-speed homogenizer (5000 rpm) for 20 min to obtain the nanoparticle slurry. The remaining procedures were the same as in Example 1. The specific procedures will not be repeated here.

[0041] Comparative Example 4 Based on Example 1, the mixed nanoparticles were adjusted to consist of nano-titanium dioxide and nano-alumina in a weight ratio of 1:3, and the corresponding nanocomposite slurry was prepared using the same method. The remaining procedures are the same as in Example 1. Specific details will not be elaborated further.

[0042] Comparative Example 5 Based on Example 1, except that the weight of the organosilicon-modified acrylate copolymer emulsion was adjusted to 20 parts and the weight of the silica sol was adjusted to 30 parts, the rest was the same as in Example 1. The specific scheme will not be described in detail.

[0043] Comparative Example 6 Based on Example 1, except that the weight parts of silica aerogel powder slurry are adjusted to 14 parts and the weight parts of aluminum silicate short fibers are adjusted to 3 parts, the rest is the same as in Example 1. The specific scheme will not be described in detail.

[0044] Comparative Example 7 Based on Example 1, except that the weight part of the nanocomposite slurry is increased to 25 parts, the rest is the same as in Example 1. The specific scheme will not be described in detail.

[0045] Experimental Example 1 This experiment is a thermal insulation performance test to examine the protective effect of the coating on the substrate material. Since wood has poor thermal conductivity and is not convenient for temperature measurement, tinplate (0.4 mm thick) was used as a substitute for wood as the substrate. The coatings obtained in Examples 1-3 and Comparative Examples 1-4 were uniformly coated on the tinplate, with a coating thickness of 300 μm.

[0046] The test method is as follows: In a windless room (room temperature 23~25℃), hold a flame torch (outer flame temperature 1300℃~1400℃), aim the flame at the center of the coating, and let the outer flame burn onto the coating. Use an infrared thermometer to measure the temperature of the back of the tinplate (i.e. the side without coating) in real time. The time required to heat up to 200℃ (the ignition point of commonly used furniture wood is 200~330℃, such as the ignition point of cedar wood is about 210℃) is used as the heat insulation time to characterize the heat insulation performance of the coating.

[0047] Currently, approximately 88.5% of flame-retardant coatings developed for wood-based substrates are water-based (according to a report by the Global Info Research team). These materials are typically developed for standard fire tests (such as fires caused by matches or small woodpile ignition sources) and do not consider extreme situations (such as localized, sustained high-temperature flame jets). Therefore, in extreme situations, they are difficult to use to slow down indoor wood combustion and provide people with golden time to extinguish the fire or escape. Based on this, considering the sustained, jet-like combustion of indoor combustibles in extreme situations, the inventors set the primary research and development target of the coating as being able to keep the temperature of the wood substrate under the coating below its ignition point within 30 minutes under a 1300-1400℃ flame torch, thus preventing the wood from spontaneously combusting or being ignited, which could lead to a worsening of the fire.

[0048] As shown in Table 1, the coatings obtained in Examples 1-3 exhibit better thermal insulation performance, requiring only 32-34 minutes to reach 200°C. In contrast, the coatings in Comparative Examples 1-4 show poorer thermal insulation performance, requiring only 2-11 minutes to reach 200°C. In the comparative examples, replacing the silicone-modified acrylate copolymer emulsion with an acrylate emulsion resulted in the substrate material reaching 200°C in just 2 minutes. This may be because the silicone-modified acrylate copolymer emulsion can collaborate with silica sol. After the polymer emulsion undergoes initial carbonization, the silica sol transforms into a robust silica ceramic framework at high temperatures, buffering further carbonization and forming a relatively stable and fixed structure. This framework, combined with fumed silica aerogel, multi-graded hollow ceramic microspheres, and mixed nanoparticles, constructs a high-temperature resistant solid framework. In contrast, the acrylate emulsion exhibits poor collaboration with silica sol, making it difficult to quickly form a buffer structure at high temperatures. This prevents it from constructing a high-temperature resistant framework with other substances, leading to rapid burn-off of the coating and a rapid rise in the temperature of the substrate material. As can be seen from Comparative Examples 2 to 4, the selection of nanomaterials and the particle size of hollow ceramic microspheres are also crucial when constructing a high-temperature resistant framework. This may be because the physical structure formed by the micro-nano filling material in this system affects the quality of thermal barrier formation, and the synergistic effect between the scattering and reflection properties of each material is also key.

[0049] The substrate used in this test was tinplate to better quantify the thermal insulation performance of the coating. Based on the experimental results in Table 1, the inventors used cedar wood (furniture wood with a relatively low ignition point) as the base material and coated the entire surface of the wood sample (30mm thick) with a 300μm coating. In a windless room (room temperature 23~25℃), a flame torch (outer flame temperature 1300℃~1400℃) was used to aim the flame at the center of the coating, and the outer flame was directed onto the coating. The time required for the wood sample to burn was recorded (based on the time it takes for the wood to ignite). As shown in Table 2, the burning time for Examples 1 to 3 was 38~40 minutes, indicating that the obtained coating has a good thermal insulation effect; while the burning time for Comparative Examples 1 to 4 was only 3~13 minutes, indicating a poor thermal insulation effect. However, to the best of our knowledge, some water-based coatings can also keep the temperature of the base material below 200℃ for a long time in environments with temperatures exceeding 1000℃, but the required coating thickness is usually higher than 5mm, making them unsuitable for coating furniture wood. Although the coatings obtained in Comparative Examples 2-4 could keep the substrate temperature below 200°C within minutes and tens of minutes, demonstrating good heat insulation, subsequent tests by the inventors revealed that the coatings cracked after flame burning, and their wear resistance also decreased significantly, failing to meet the inventors' research requirements. See Experimental Example 2 for details.

[0050] Table 1 Table 2 Experimental Example 2 This experiment investigated the abrasion resistance of the coatings in Examples 1-3 and Comparative Examples 1-4 before and after multiple rounds of spraying treatment (after each round of spraying treatment, the coating was cooled to room temperature before the next round of spraying treatment). The spraying treatment time for each group was slightly shorter than the combustion time for each group. Specifically, for Examples 1-3, the spraying treatment time was 30 minutes, and for Comparative Examples 1-4, the spraying treatment time was 3 minutes.

[0051] The substrate material was cedar wood, the substrate sample thickness was 30 mm, and the coating thickness was 300 μm. The test method followed GB / T4893.8-2021 "Determination of Abrasion Resistance of Furniture Surface Coating", and the test conditions were: CS-10 grinding wheel, 500g load, 500 revolutions. The experimental results are shown in Table 3.

[0052] Table 3 Note: " / " indicates that after one round of spraying and burning, at least one visible crack has appeared, and no further spraying and burning treatment will be carried out.

[0053] As shown in Table 3, the abrasion resistance of Comparative Examples 1 to 4 is mostly at the "high abrasion resistance level" (mass loss ≤50mg), which, considering abrasion resistance alone, has certain application value. However, after one round of spraying and burning treatment, not only did the mass loss increase significantly, but visible cracks also appeared. This indicates that the coatings of Comparative Examples 1 to 4 have poor durability under high temperature conditions. Even if the base wood does not burn after just one extreme high-temperature exposure, the corresponding coating still needs to be replaced.

[0054] Experimental Example 3 In developing this invention, the inventors prioritized the insulation time as the primary research indicator. Based on this, they also investigated the coating's delamination and stability under temperature and humidity changes. Comparative Examples 1-4 were not included in this experiment because they did not meet the insulation time requirements. This experiment examines the impact of slight adjustments to the formulation (i.e., Comparative Examples 5-7) on delamination and stability under temperature and humidity changes, based on Examples 1-3.

[0055] Stratification test method: At room temperature (the day and night temperature during the test period is in the range of 15~22℃), place the sample (prepared according to Experiment Example 1, the substrate material is cedar wood) in a cool place for 36 hours and observe whether stratification occurs.

[0056] Temperature and humidity change stability test method: The sample (prepared according to Experiment Example 1, the base material is cedar) is first placed in a drying oven at 60℃ for 2 hours, then allowed to cool to room temperature, and then placed at 25℃ and 95% RH for 2 hours. This cycle is repeated 3 times. After that, the presence of microcracks is observed by visual inspection.

[0057] The experimental results are shown in Table 4. Examples 1-3 showed no stratification and good stability under temperature and humidity changes. Comparative Examples 5-6 showed stratification, which may be because the addition amounts of silica sol, organosilicon-modified acrylate copolymer emulsion, silica aerogel, and aluminosilicate fibers have a significant impact on the thixotropic properties of the system. Changes in the system cause the corresponding components to float and settle, resulting in stratification. In the system of this invention, the inorganic filler content is relatively high. Slightly increasing the amount of nanocomposite slurry added (see Comparative Example 7) reduces the stability under temperature and humidity changes. After three cycles of temperature and humidity treatment, microcracks appeared in the coating. This indicates that the amount of nanocomposite slurry added in this invention is controlled relatively sluggishly.

[0058] Table 4 Based on the experimental results in Table 1, the inventors conducted long-term temperature and humidity stability tests on the coatings obtained in Examples 1-3. The test method was as follows: During the day, the samples (prepared according to Experimental Example 1, with cedar wood as the substrate material) were first placed in a drying oven at 60°C for 2 hours, then allowed to cool to room temperature, and then placed at 25°C and 95% RH for 2 hours. This cycle was repeated 3 times. After that, the samples were left at room temperature overnight, and the above treatment was repeated the next day. This cycle was repeated continuously. Within 12 days, no microcracks appeared in the coatings obtained in Examples 1-3.

[0059] Experiment Example 4 Liquid resistance tests were conducted on the samples prepared with the coatings of Examples 1-3 (prepared according to Experimental Example 1, with cedar wood as the substrate material). The standard used was GB / T 30648.1-2014. Acid resistance was tested using a 5% (v / v) hydrochloric acid solution, and alkali resistance was tested using a 5% (w / w) sodium hydroxide solution. The test temperature was 23±2℃, and the treatment time was 48 hours. After treatment, the presence of bubbles or obvious changes in appearance (discoloration and spots) was observed. The experimental results showed that no bubbles, discoloration, or spots appeared on the samples prepared with the coatings of Examples 1-3 after acid or alkali treatment. This indicates that the coatings obtained in Examples 1-3 have good liquid resistance and meet the requirements for daily use.

Claims

1. A highly weather-resistant water-based modified acrylic coating, characterized in that, The coating comprises the following raw materials in parts by weight: The composition includes: 25 parts of organosilicon-modified acrylate copolymer emulsion, 25 parts of silica sol, 29-32 parts of multi-graded hollow ceramic microspheres, 5 parts of alumina whiskers, 5 parts of alumina short fibers, 19-21 parts of nanocomposite slurry, 11-13 parts of fumed silica aerogel powder slurry, 1.5 parts of dispersant, 0.5 parts of defoamer, 0.3 parts of wetting agent, and 20 parts of deionized water. The multi-graded hollow ceramic microspheres are obtained by mixing hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm in a weight ratio of 5:3:

3. The nanocomposite slurry is prepared by mixing nano titanium dioxide, nano aluminum oxide, hexagonal boron nitride and nano zinc borate in a weight ratio of 1:3 to 5:5:4 to obtain mixed nano powder, which is then dispersed by mixing with deionized water and a dispersant. The fumed silica aerogel slurry is obtained by mixing fumed silica aerogel powder with ethanol and water and stirring until homogeneous.

2. The high weather-resistant water-based modified acrylic coating according to claim 1, characterized in that, The dispersant is EFKA-4580; the defoamer is obtained by mixing BYK-028 and BYK-024 in a weight ratio of 2:

1.

3. The high weather-resistant water-based modified acrylic coating according to claim 2, characterized in that, The wetting agent is TEGO® Wet 270.

4. A high weather-resistant water-based modified acrylic coating according to claim 1 or 3, characterized in that, The coating comprises the following raw materials in parts by weight: The following ingredients are listed: 25 parts of organosilicon-modified acrylate copolymer emulsion, 25 parts of silica sol, 30 parts of multi-graded hollow ceramic microspheres, 5 parts of alumina whiskers, 5 parts of alumina short fibers, 20 parts of nanocomposite slurry, 12 parts of fumed silica aerogel powder slurry, 1.5 parts of dispersant, 0.5 parts of defoamer, 0.3 parts of wetting agent, and 20 parts of deionized water. The multi-graded hollow ceramic microspheres are obtained by mixing hollow ceramic microspheres with particle sizes of 10μm, 30μm and 50μm in a weight ratio of 5:3:

3. The nanocomposite slurry is prepared by mixing nano-titanium dioxide, nano-alumina, hexagonal boron nitride, and nano-zinc borate in a weight ratio of 1:3:5:4 to obtain mixed nanoparticles, which are then dispersed by mixing with deionized water and a dispersant.

5. The high weather-resistant water-based modified acrylic coating according to claim 4, characterized in that, The particle size distribution of nano-titanium dioxide, nano-alumina, and nano-zinc borate is 100~200nm, and the particle size distribution of hexagonal boron nitride is 50~100nm.

6. A high weather-resistant water-based modified acrylic coating according to claim 1 or 5, characterized in that, The organosilicon-modified acrylate copolymer emulsion has a solid content of 50% w / w, and the silica sol has a SiO2 content of 30% w / w.

7. The high weather-resistant water-based modified acrylic coating according to claim 6, characterized in that, The fumed silica aerogel slurry is obtained by the following method: fumed silica aerogel powder, ethanol and water are mixed in a weight ratio of 5:4:1 and stirred at 400 rpm for 20 min.

8. A method for preparing a highly weather-resistant water-based modified acrylic coating, characterized in that, The coating is a high weather-resistant water-modified acrylic coating as described in any one of claims 1 to 7; the preparation method includes the following steps: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. Under stirring conditions, slowly add fumed silica aerogel powder slurry. After the addition is complete, continue stirring until uniform. Then, under stirring conditions, slowly add nanocomposite slurry. After the addition is complete, continue stirring until uniform. Then, under stirring conditions, slowly add alumina whiskers. After the addition is complete, continue stirring until uniform. (2) Under stirring conditions, slowly add silica sol, and continue stirring until homogeneous after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion, and continue stirring until homogeneous after the addition is complete. (3) Under stirring conditions, slowly add multi-graded hollow ceramic microspheres. After the addition is complete, continue stirring until uniform. Then slowly add aluminum silicate short fibers. After the addition is complete, continue stirring until uniform. (4) Adjust the pH to 8.5 with ammonia water, add the remaining 50% of the formula amount of defoamer and wetting agent under stirring conditions, continue to stir evenly after the addition is complete, filter to remove impurities and let stand to defoam, and the coating is obtained.

9. The method for preparing a high weather-resistant water-based modified acrylic coating according to claim 8, characterized in that, The preparation method includes the following steps: (1) In a stirrer, add deionized water, dispersant and 50% of the formula amount of defoamer. At a stirring speed of 400 rpm, slowly add fumed silica aerogel powder slurry. After the addition is complete, increase the stirring speed to 800 rpm and stir for 30 min. Then, at a stirring speed of 1500 rpm, slowly add nanocomposite slurry and keep for 30 min after the addition is complete. Then, at a stirring speed of 400 rpm, slowly add alumina whiskers and keep for 30 min after the addition is complete. (2) Add silica sol slowly at a stirring speed of 400 rpm, and keep for 10 min after the addition is complete. Then slowly add organosilicon-modified acrylate copolymer emulsion and keep for 15 min after the addition is complete. (3) Keep the stirring speed at 400 rpm, slowly add multi-grade hollow ceramic microspheres, keep for 15 min after the addition is complete, then slowly add aluminum silicate short fibers, keep for 15 min after the addition is complete. (4) Adjust the pH to 8.5 with ammonia water, keep the stirring speed at 400 rpm, add the remaining 50% of the formula amount of defoamer and wetting agent, keep for 30 minutes after the addition is complete, filter with a 100-200 mesh filter, and let stand for 24 hours to defoam before obtaining the coating.

10. The use of the coating as described in any one of claims 1 to 7, or the coating prepared by the preparation method described in claim 8 or 9, as a coating material for wood-based furniture.

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