A preparation method for a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material

Abstract

The present invention belongs to the technical field of hydrophobic coating material preparation, and discloses a preparation method of a high-performance water-based acrylic-based soft ceramic super-hydrophobic coating material, comprising the following steps: (1) placing a glass slide in a beaker filled with anhydrous ethanol for cleaning, and then drying for standby use; (2) placing silica particles in a beaker, adding anhydrous ethanol, stirring, and dispersing in an ultrasonic vibration cleaning machine, then dropping FAS-17 into the beaker, and placing it in a water bath until the anhydrous ethanol is completely evaporated; (3) adding acrylic resin, polyurethane and anhydrous ethanol into a beaker, and then adding the modified silica into the beaker, adding γ-aminopropyl triethoxysilane, cellulose nanocrystals and epoxy resin under stirring, and then stirring under water bath conditions; (4) applying the coating on a glass slide, and obtaining a super-hydrophobic coating material after curing. The material of the present invention has excellent properties such as wear resistance and heat resistance, and has great application potential in the fields of decoration and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrophobic coating material preparation, and in particular relates to a method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material. Background Art

[0002] Soft ceramic tiles produced using existing technology are undoubtedly a trendsetting new building and decoration material, integrating environmental protection concepts with technological innovation. The preparation of this material relies primarily on a series of carefully selected raw materials, including meticulously processed construction waste and industrial waste residues, which, once considered a burden, are given new life here; specially modified clay, which imparts the soft ceramic tiles with unique physical properties; and carefully selected quartz sand and calcium carbonate powders, which are cleverly mixed with a specific proportion of adhesive. Precise proportioning and process control ensure the uniformity and stability of the material. This series of raw materials undergoes a complex process of low-temperature baking and radiation cross-linking in a specialized temperature-controlled molding system, ultimately forming a building and decoration material that is both environmentally friendly and low-carbon, as well as exceptionally flexible.

[0003] Compared to traditional hard ceramics, soft ceramic tiles offer significant advantages. Their lighter and thinner material significantly reduces the overall weight of the product, facilitating handling and transport. This also simplifies installation, reducing both construction difficulty and costs. Furthermore, soft ceramic tiles exhibit impressive impact resistance, resisting breakage even from accidental impacts or external forces. This significantly enhances the product's durability and lifespan, providing users with a more durable and stable decorative effect.

[0004] However, when soft ceramic tiles are used in outdoor architectural decoration, they also face challenges. The natural environment is complex and changeable. Soft ceramic tiles must not only withstand the baptism of wind and rain, but also face the corrosive effects of acid and alkaline components in rainwater. Further complicating matters, as the ambient humidity fluctuates, soft ceramic tiles may experience hygroscopic expansion or dehydration contraction. This repeated volume change can easily cause surface cracking, which in turn seriously affects the overall performance and lifespan of the soft ceramic tiles. Therefore, how to maintain the original advantages of soft ceramic tiles while improving their adaptability to the external environment has become a pressing issue.

[0005] In this context, super-hydrophobic coating materials applied to soft ceramic tiles are particularly important. This coating acts as an invisible shield, effectively isolating the tiles from moisture and acidic and alkaline substances, protecting them from damage. Currently, in the field of super-hydrophobic material research, polymer nanocomposite super-hydrophobic materials have attracted much attention due to their unique properties. This type of material forms a super-hydrophobic composite material with a dense structure and excellent performance by embedding inorganic nanoparticles of various forms into a polymer matrix in a highly dispersed and filled manner. This composite material not only has excellent hydrophobic properties, but also can improve the wear resistance, weather resistance and self-cleaning properties of soft ceramic tiles to a certain extent, providing a more solid guarantee for the application of soft ceramic tiles in the field of outdoor architectural decoration. Summary of the Invention

[0006] The present invention provides a method for preparing a high-performance water-based acrylic acid-based soft ceramic tile super-hydrophobic coating material. The material has excellent performance and can meet the application requirements in the field of decoration.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] A method for preparing a high-performance water-based acrylic-based soft ceramic super-hydrophobic coating material comprises the following steps:

[0009] (1) Place the glass slide in a beaker of anhydrous ethanol for ultrasonic cleaning, and then place the cleaned glass slide in an oven for drying.

[0010] (2) Place the silica particles in a beaker, add anhydrous ethanol to the beaker, stir, and disperse them evenly in an ultrasonic vibration cleaning machine. Then, drop FAS-17 (1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane) into the beaker, place it in a water bath and stir until all the anhydrous ethanol evaporates. Cool it to obtain the modified silica for use.

[0011] (3) Add acrylic resin, polyurethane and anhydrous ethanol to a beaker, and then stir in a water bath. Add the modified silica to the beaker, and then stir in a water bath. Then, add γ-aminopropyltriethoxysilane, cellulose nanocrystals and epoxy resin, and then stir in a water bath and cool to room temperature.

[0012] (4) The coating is applied on a glass slide by coating, and after curing at room temperature, a high-performance water-based acrylic-based soft ceramic super-hydrophobic coating material is obtained.

[0013] Preferably, in step (1), the glass slide is placed in a beaker containing anhydrous ethanol and ultrasonically cleaned for 10-15 minutes.

[0014] Preferably, in step (2), the mixture is stirred for 15 minutes and then placed in an ultrasonic vibration cleaning machine.

[0015] Preferably, after stirring in step (2), the mixture is dispersed in an ultrasonic vibration cleaning machine for 10-15 minutes to achieve uniform dispersion.

[0016] Preferably, in step (3), acrylic resin, polyurethane and anhydrous ethanol are added to a beaker and stirred in a water bath at 35-40° C. for 1 h.

[0017] Preferably, in step (3), the modified silica is added to a beaker and stirred in a water bath at 35-40° C. for 30 minutes.

[0018] Preferably, in step (3), γ-aminopropyltriethoxysilane, cellulose nanocrystals and epoxy resin are added thereto, stirred in a water bath at 35-40° C. for 30-35 minutes and then cooled to room temperature.

[0019] Preferably, the curing time at room temperature in step (4) is 10-15 minutes.

[0020] The preparation technology principle of the high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material of the present invention is as follows:

[0021] 1. Specific functions of raw materials

[0022] 1. Glass slide

[0023] The glass slide serves as the substrate for the coating throughout the entire preparation process. It provides a flat and clean surface for subsequent coating application, allowing the coating to adhere evenly and facilitating observation and testing of coating properties.

[0024] 2. Silica particles

[0025] Silica particles are a key ingredient in constructing the surface microstructure of super-hydrophobic coatings. Nano-sized silica particles have a large specific surface area, creating a microscopic roughness on the coating surface. This roughness is a key factor in achieving super-hydrophobic properties. It increases the contact angle between water and the coating surface, causing water to form beads and roll on the coating surface, removing dust and other contaminants and achieving a self-cleaning function. Silica particles also enhance the strength and toughness of the coating material, improving the coating's wear resistance.

[0026] 3. FAS-17 (1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane)

[0027] FAS-17 is primarily used for surface modification of silica particles. It has an extremely low surface energy and chemically bonds with the hydroxyl groups on the silica particles, forming a layer of low-energy fluorocarbon chains. FAS-17 modification further reduces the surface energy of the coating, making it more difficult for water to spread across the surface, thereby significantly improving the coating's hydrophobicity.

[0028] 4. Acrylic resin and polyurethane

[0029] Acrylic resins offer excellent weather resistance, chemical resistance, and adhesion, providing the coating with essential mechanical properties and chemical stability. Polyurethane, on the other hand, offers excellent flexibility and abrasion resistance, enhancing the coating's elasticity and impact resistance. The composite resin formed by the two acts as the coating's matrix, providing a stable dispersion environment for the other raw materials. Upon curing, it forms a continuous film structure, firmly binding the other raw materials together and imparting overall strength and stability to the coating.

[0030] 5.γ-aminopropyltriethoxysilane

[0031] γ-Aminopropyltriethoxysilane is a coupling agent. It contains an ethoxy group on one end that reacts with the surface of silica particles, and an amino group on the other end that reacts with acrylic resins and polyurethanes. In this way, γ-aminopropyltriethoxysilane can establish a chemical bond between the inorganic silica particles and the organic resin matrix, strengthening the interfacial bonding between the inorganic and organic phases and improving the overall performance of the coating, particularly its adhesion and water resistance.

[0032] 6. Cellulose Nanocrystals (CNC)

[0033] Cellulose nanocrystals possess high strength, high modulus, and excellent biocompatibility. In coatings, CNCs can provide both reinforcement and toughening. Dispersed within the resin matrix, they form a nano-reinforced network structure that hinders crack propagation and improves the coating's crack resistance. Furthermore, CNCs improve the coating's rheological properties, facilitating uniform coating application.

[0034] 7. Epoxy resin (EP)

[0035] Epoxy resin has excellent adhesion, chemical resistance, and mechanical properties. In coatings, epoxy resin can undergo cross-linking reactions with acrylic resin, polyurethane, and γ-aminopropyltriethoxysilane to form a denser three-dimensional network structure, further improving the coating's hardness, wear resistance, and chemical resistance, while also enhancing its structural stability.

[0036] 2. Synergistic Effect of Raw Materials

[0037] 1. Synergy between silica particles and FAS-17

[0038] The silica particles provide the coating's surface with microscopic roughness, while FAS-17 reduces the coating's surface energy. The synergistic effect of these two factors creates a coating with both a suitable microstructure and extremely low surface energy, achieving superhydrophobic properties. For example, the water contact angle of a silica particle coating without FAS-17 modification might be only around 120°, but after modification with FAS-17, the water contact angle can be increased to over 160°.

[0039] 2. Synergy between composite resin and modified silica particles

[0040] The composite resin composed of acrylic resin and polyurethane provides an excellent dispersion medium and bonding matrix for the modified silica particles. The modified silica particles are evenly dispersed in the composite resin, enhancing the coating's hydrophobicity while also improving its strength and toughness. The bonding effect of the composite resin ensures the silica particles adhere securely to the coating, preventing particle loss and ensuring the coating's long-term stability and wear resistance.

[0041] 3. Bridging effect of γ-aminopropyltriethoxysilane

[0042] γ-Aminopropyltriethoxysilane chemically connects the silica particles and the composite resin, strengthening the interfacial bonding between them. This bonding allows the inorganic and organic phases to work more effectively together, enhancing the overall performance of the coating. For example, when subjected to external forces, the presence of γ-aminopropyltriethoxysilane better transfers stress between the silica particles and the composite resin, reducing cracking and flaking of the coating.

[0043] 4. Synergy between CNC and EP and other raw materials

[0044] The addition of CNC and EP further optimizes the coating's performance. The CNC's nano-reinforced network interweaves with the composite resin and silica particles, enhancing the coating's crack resistance. The epoxy resin cross-links with the other raw materials, forming a three-dimensional network that tightly binds the CNC, silica particles, and composite resin together, enhancing the coating's hardness, wear resistance, and structural stability.

[0045] 3. Necessity and importance of process parameter control

[0046] 1. Ultrasonic cleaning time of slides (10-15 minutes)

[0047] If the ultrasonic cleaning time is too short, oil and impurities on the slide surface may not be completely removed, which will affect the adhesion between the coating and the slide and cause the coating to peel off during subsequent use. If the cleaning time is too long, it may damage the slide surface, which is also detrimental to the adhesion and performance of the coating. After 10-15 minutes of ultrasonic cleaning, the slide surface can be clean and undamaged, providing an excellent foundation for the coating to be applied evenly and firmly.

[0048] 2. Silica particle stirring and ultrasonic dispersion time

[0049] Stir for 15 minutes and then ultrasonically disperse for 10-15 minutes: The purpose of stirring is to preliminarily disperse the silica particles in anhydrous ethanol in preparation for subsequent ultrasonic dispersion. If the stirring time is too short, the particles may not be fully dispersed, resulting in poor subsequent ultrasonic dispersion effect. Ultrasonic dispersion can further break up the agglomeration of the particles and make the particles evenly dispersed in the solution. If the ultrasonic dispersion time is too short, the particles will be unevenly dispersed, which will affect the uniformity of the coating surface roughness and further affect the hydrophobicity and other properties of the coating. If the ultrasonic time is too long, the particle size may become smaller and the original structure of the particles may be destroyed, which is also not conducive to the realization of coating performance. After optimizing the stirring and ultrasonic dispersion time, the silica particles can be evenly dispersed, providing good conditions for subsequent surface modification and coating preparation.

[0050] 3. Composite resin stirring temperature and time

[0051] Stir for 1 hour in a 35-40°C water bath: Within this temperature and time range, acrylic resin and polyurethane can fully dissolve and mix to form a uniform solution. If the temperature is too low, the resin will dissolve slowly and the mixing will be uneven, which will affect the performance of the coating. If the temperature is too high, the resin may partially cross-link or degrade, which is also not conducive to improving the performance of the coating. If the stirring time is too short, the resin will not be fully mixed, resulting in unstable coating performance; if the stirring time is too long, it will not only waste time and energy, but may also introduce impurities or cause excessive volatilization of the solution. Stirring for 1 hour in a 35-40°C water bath can ensure that the composite resin is fully mixed, providing a stable matrix for subsequent coating preparation.

[0052] 4. Stirring time after adding modified silica (30 min)

[0053] After adding the modified silica to the composite resin, it needs to be stirred for a certain period of time to ensure uniform dispersion. If the stirring time is too short, the silica particles may not be fully dispersed in the resin, resulting in uneven coating properties. If the stirring time is too long, the modified layer on the silica particles may be damaged, affecting the hydrophobicity of the coating. A stirring time of 30 minutes ensures that the modified silica particles are evenly dispersed in the composite resin, ensuring uniform and stable coating properties.

[0054] 5. Stirring time after adding γ-aminopropyltriethoxysilane, CNC and EP (30-35 minutes)

[0055] After adding γ-aminopropyltriethoxysilane, CNC, and EP, they need to be thoroughly stirred to allow them to fully react and mix with the composite resin and modified silica. γ-aminopropyltriethoxysilane requires time to chemically bond with the silica particles and resin, while CNC and EP also require time to interact with the other raw materials to form a stable structure. Too short a stirring time will result in inadequate reaction and mixing, affecting the overall performance of the coating. Too long a stirring time may cause the system to overreact or introduce defects such as unnecessary bubbles. A stirring time of 30-35 minutes ensures that all raw materials fully react and mix, forming a stable coating system.

[0056] 6. Room temperature curing time (10-15 minutes)

[0057] Room temperature curing time is crucial to the performance of a coating. If the curing time is too short, the coating may not fully cure, resulting in poor hardness, abrasion resistance, and water resistance. If the curing time is too long, cracks or other defects may form on the coating surface, affecting its appearance and performance. A room temperature curing time of 10-15 minutes allows the coating to fully cure, resulting in a superhydrophobic coating with excellent performance.

[0058] By optimizing the raw material dosages and process parameters, the resulting high-performance, water-based, acrylic-based super-hydrophobic coating for soft ceramic tiles exhibits exceptional overall performance. Its optimal average static water contact angle reaches 162.689°. It exhibits excellent resistance to acid and alkali solutions, high and low temperatures, abrasion resistance, and self-cleaning properties, making it suitable as a protective coating for outdoor decorative materials and possessing significant potential for application in the decorative field. This performance improvement, the result of the synergistic effect of the various raw materials and optimized process parameters, is an unexpected technical achievement.

[0059] The technical solution of the present invention has the following technical advantages compared with the prior art:

[0060] (1) The present invention prepares a super-hydrophobic coating material by adding nano-scale silica particles modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane to a composite resin and adding γ-aminopropyltriethoxysilane. The optimum roughness and optimal hydrophobicity are found by controlling the amount of nano-scale silica particles added in terms of roughness and particle size. Nano-scale silica particles can not only enhance the strength and toughness of the super-hydrophobic coating material, but also make the coating have higher hydrophobicity and certain wear resistance. A super-hydrophobic coating material with stable properties and certain wear resistance can be obtained. The introduction of CNC and EP improves the ultimate crack resistance and structural stability of the coating.

[0061] (2) Nano-sized silica particles modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17) were filled into a waterborne acrylic acid (AA) and waterborne polyurethane (WPU) composite resin to prepare a waterborne acrylic polyurethane-SiO2 organic-inorganic interpenetrating network. X-ray photoelectron spectroscopy (XPS) showed that FAS-17 was successfully filled into SiO2. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that the synthesized coating had a uniform morphology and neat peak-valley structure, providing strong evidence for the super-hydrophobic properties of the coating. The optimal average static water contact angle was 162.689°. Tests of acid and alkali solution resistance, high and low temperature environment resistance, wear resistance and self-cleaning all proved that the prepared super-hydrophobic coating material can be used as a protective coating for outdoor decorative materials. The test results using a thermal analyzer showed that the super-hydrophobic coating material had good thermal properties. In summary, the comprehensive performance of the high-performance water-based acrylic-based soft ceramic tile super-hydrophobic coating material prepared by the present invention has great application potential in the field of decoration. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is the experimental flow chart;

[0063] Figure 2 The static contact angle results with water under different conditions (A is KH550 as a variable, B is SiO2 as a variable, C is CNC as a variable, and D is EP as a variable);

[0064] Figure 3 The mass wear of super-hydrophobic coating materials made of different resin ratios (A) and the comparison of static contact angle with water before and after wear (B);

[0065] Figure 4 The scanning electron microscope images of SiO2 doped with different masses (A is 0.25g, B is 0.3g, and C is 0.35g);

[0066] Figure 5The particle size (A) and zeta potential (B) of the superhydrophobic coating material AW-0.24;

[0067] Figure 6 This is the XPS graph of the super-hydrophobic coating material AW-0.24 (A is the total spectrum, B is C1s, and C is O1s);

[0068] Figure 7 AFM images of the super-hydrophobic coating material AW-0.24 (A is a 3D image, B is a 2D image);

[0069] Figure 8 The changes in the water contact angle of the super-hydrophobic coating material AW-0.24 under the influence of acid and alkaline solutions (A), and the changes in the water contact angle of the coating under the influence of high and low temperatures (B);

[0070] Figure 9 This is a self-cleaning diagram of the super hydrophobic coating material AW-0.24, where Figure 9 (A) Experimental image showing the superhydrophobicity of the superhydrophobic coating material AW-0.24. Figure 9 (B) is the experimental picture before the simulated coating is covered with dust. Figure 9 (C) is the experimental picture after the dust is washed away by the water flow, which can demonstrate the self-cleaning ability of the coating;

[0071] Figure 10 TG, DSC, and DTG graphs of the thermal properties of the superhydrophobic coating material AW-0.24;

[0072] Figure 11 This is a diagram showing the influence of different coating methods on the static water contact angle of superhydrophobic coating material AW-0.24. DETAILED DESCRIPTION

[0073] The present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be emphasized that the following description is merely illustrative and is not intended to limit the scope of the present invention and its application.

[0074] 1. Experimental

[0075] 1.1 Materials and Reagents

[0076] Water-based acrylic resin. Cellulose nanocrystals. Water-based polyurethane (F0402), Shenzhen Jitian Chemical Co., Ltd. Anhydrous ethanol (analytical grade), Sinopharm Chemical Reagent Co., Ltd. Nanosilica (20 nm), Zhenhan New Materials (Suzhou) Co., Ltd. 1H,1H,2H,2H-perfluorodecyltriethoxysilane (96%, analytical grade), Shanghai MacLean Biochemical Technology Co., Ltd. Water-based epoxy resin emulsion, Shenyang Dongyan Paint Decoration Co., Ltd. γ-Aminopropyltriethoxysilane (98%, analytical grade), Shandong Keyuan Biochemical Co., Ltd. Deionized water (pure water, homemade). Sodium hydroxide (analytical grade), Shanghai MacLean Biochemical Technology Co., Ltd.

[0077] 1.2 Coating preparation (see Figure 1 )

[0078] (1) Preprocessing

[0079] Place the slide in a beaker of anhydrous ethanol and ultrasonically clean it for 10 minutes. Then, place the cleaned slide in an oven to dry it for later use.

[0080] Weigh 3 g of silica particles and place them in a 50 mL beaker. Then add 30 mL of anhydrous ethanol to the beaker, stir for 15 minutes, and disperse it in an ultrasonic vibration cleaner for 15 minutes to make it evenly dispersed. Then add 5 μL of FAS-17 dropwise to the beaker, place it in a 60°C water bath and stir until all the anhydrous ethanol is evaporated. Cool it to obtain the modified silica for use.

[0081] (2) Preparation of coating

[0082] As shown in Table 1, a certain proportion of water-based acrylic resin (AA), water-based polyurethane (WPU) and 10 mL of anhydrous ethanol were added to a 25 mL beaker and stirred in a water bath at 35°C for 1 hour. 0.3 g of modified silica was weighed and added to the beaker. After stirring in a water bath at 35°C for 30 minutes, 60 μL of γ-aminopropyltriethoxysilane (KH550), 10 μL of cellulose nanocrystals (CNC) and 10 μL of water-based epoxy resin (EP) were added. The mixture was stirred in a water bath at 35°C for 30 minutes and then cooled to room temperature.

[0083]

[0084] The coating was applied on a glass slide using different coating methods and cured at room temperature for 10 minutes to obtain a transparent super-hydrophobic coating material.

[0085] 1.3 Characterization methods

[0086] 1.3.1 Determination of contact angle

[0087] The static water contact angle of the latex coating on the glass plate was analyzed using a contact angle meter (SDC-350, CHN) at 25°C using the sessile drop method. The angles obtained at more than 10 different locations on each sample surface were averaged.

[0088] 1.3.2 Particle size and potential determination

[0089] The particle size and potential of the latex were analyzed by using a nanoparticle size and zeta potential analyzer (Malvern Zetasizer Nano ZS90, UK) after diluting the high solid phase emulsion at least 50 times with deionized water.

[0090] 1.3.3 Scanning electron microscopy morphology measurement

[0091] The surface and cross-sectional morphologies of the emulsions were studied using a Hitachi-S520 scanning electron microscope (SEM).

[0092] 1.3.4 Atomic force microscopy measurement

[0093] The surface roughness of the coating is measured using an atomic force microscope (AFM, Bruker Nano Lnc, GER). The XYZ three-axis closed-loop scanner, with a resolution of 90μm in the XY direction and 10μm in the Z direction, can meet the requirements of atomic imaging testing.

[0094] 1.3.5 X-ray Photoelectron Spectroscopy Test

[0095] An X-ray photoelectron spectrometer (XPS, Thermo Fisher, USA) with an energy range of 0–5000 eV was used to measure the chemical composition or elemental composition of the coatings.

[0096] 1.3.6 Adhesion test

[0097] A 50 g weight was loaded on the coating, and the coating was placed on 800 grit sandpaper and subjected to tangential uniform motion for 100 mm to test the wear resistance of the coating.

[0098] 1.3.7 Corrosion resistance test

[0099] The corrosion resistance of the coating was tested by immersing it in acid and alkali solutions. The coating was placed in a pH = 5 HCl solution and a 5% wt NaOH solution, and the coating was immersed for 0-12 hours respectively. The change in the water contact angle of the coating was observed over time.

[0100] 1.3.8 Weather resistance test

[0101] The weather resistance of the coating is tested in high and low temperature environments, and the temperature resistance of the coating is tested by standing it at +100℃ and -20℃ for 0-10 days.

[0102] 1.3.9 Self-cleaning test

[0103] The self-cleaning properties of the coating were tested by measuring the ability of water droplets falling on the superhydrophobic surface to remove contaminants from its surface.

[0104] 1.3.10 Test on the influence of different coating methods on coating performance

[0105] Four coating methods, namely spray coating, spin coating, pull-up coating and drop coating, were used for coating, and the hydrophobic properties of the coatings were tested to compare the effects of different coating methods on coating performance.

[0106] 1.3.11 Thermal stability determination

[0107] The thermal stability of the prepared emulsions was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) using a thermal analyzer (Netzsch TG 209 F3, GER) and a differential scanning calorimeter (TAQ2000, DSC250, USA). The samples were heated from room temperature to 1000°C at a heating rate of 10°C / min under a nitrogen atmosphere.

[0108] 2 Results and Discussion

[0109] 2.1 Results and discussion of single factor

[0110] The static water contact angle usually refers to the degree of wettability of a solid surface. It is usually measured when the liquid is stably present on the solid surface. The size of the static contact angle θ is divided into the following types:

[0111] When θ<5°, the liquid spreads completely on the solid surface, which is a superhydrophilic surface;

[0112] When 5°<θ≤90°, the liquid part spreads on the solid surface, which is a hydrophilic surface;

[0113] When 90°≤θ<150°, a small part of the liquid surface spreads on the solid surface, which is a hydrophobic surface;

[0114] When 150°≤θ<180°, the liquid is spherical on the solid surface, which is a superhydrophobic surface.

[0115] Figure 2The static contact angle of the coating and water is obtained under the single factor condition. Figure A is KH550, which is a single factor variable, B is SiO2, which is a single factor variable, C is CNC, which is a single factor variable, and D is EP, which is a single factor variable. The optimal process conditions for preparing super-hydrophobic coating materials are obtained by single factor experiments. The soft magnetic sheet hydrophobic coating obtained under the optimal process conditions is tested for static water contact angle. After three repetitions, the average value is 162.689 °, which is the optimal static water contact angle, suitable for super-hydrophobic coating materials on the surface of soft magnetic sheets.

[0116] 2.2 Wear resistance of composite resins with different proportions

[0117] Figure 3 The comparison of the mass wear of super hydrophobic coating materials made of different resin ratios and the static contact angle with water before and after wear is shown in the figure. A 50g weight is loaded on the coating, and the coating is placed on 800-grit sandpaper and subjected to a tangential uniform motion of 100mm to obtain the mass wear. First, we use Figure 3 (A) It can be seen that the wear of AW-0.24 is the smallest, indicating that it has the best wear resistance. Figure 3 (B) AW-0.24 exhibits the highest static water contact angle. This indicates that the composite resin contact angle is significantly influenced by the AA and WPU content. This is because the waterborne polyurethane has hydrophilic groups on its surface. As the number of hydrophilic groups decreases to an appropriate level, the composite coating achieves optimal hydrophobicity. Furthermore, compared to the significant decreases in static water contact angles after friction with other resins of varying ratios, AW-0.24 (i.e., 0.24g of waterborne acrylic resin AA, 0.96g of waterborne polyurethane WPU, 0.3g of FAS-17-modified silica SiO2, 60μL of γ-aminopropyltriethoxysilane KH550, 10μL of cellulose nanocrystals CNC, and 10μL of waterborne epoxy resin EP) exhibits a smaller decrease in static water contact angle after friction, indicating its superior wear resistance.

[0118] 2.3 Scanning electron microscopy analysis results

[0119] like Figure 4For doping different mass SiO2 SEM images, it can be seen that significant differences. When nano-scale silicon dioxide adds mass for 0.25g, the surface of coating is covered by composite resin substantially, and it seems that silicon dioxide less fails to form the structure of completely smooth covering for the roughness provided of coating or not enough; When nano-scale silicon dioxide adds mass for 0.3g, it can be clearly seen that silicon dioxide forms uneven, undulating surface structure, substantially without obvious protrusion and recessed roughness; When nano-scale silicon dioxide adds mass for 0.35g, it can be seen that silicon dioxide forms agglomeration, and there is obvious protrusion situation that is unfavorable for preparing the super-hydrophobic coating material of surface smoothness. Generally speaking, when nano-scale silicon dioxide adds mass for 0.3g, the morphological structure with certain roughness formed by nano-scale silicon dioxide and resin can be clearly seen, and the protrusion and recessed distribution that can obviously see coating formation are even, so that coating reaches the state of super-hydrophobicity.

[0120] 2.4 Particle size and Zeta potential analysis results

[0121] Figure 5 The graph shows the particle size and Zeta potential of the super hydrophobic coating material AW-0.24. Figure 5 (A) It can be seen that the particle size of the emulsion is more appropriate, and the Zeta potential test results Figure 5 (B) It can be seen that the coating is very stable, indicating that all emulsions have good stability.

[0122] 2.5 XPS analysis results

[0123] like Figure 6 As shown in Figure 2, the surface groups and element content distribution of the super hydrophobic coating material AW-0.24 were analyzed. Figure 6 (A) It can be seen that the super-hydrophobic coating material AW-0.24 has obvious characteristic peaks of C1s, N1s, O1s, F1s and Si2p. It can be seen that FAS-17 has successfully modified nano-SiO2 and introduced long fluorine-containing chains, so Figure 6 (B) A clear CF peak appears in the spectrum. It is this low surface energy F that provides a good chemical basis for the superhydrophobicity of the coating, and combined with the roughness provided by the SiO2 particles, it gives the composite coating an excellent superhydrophobic property. Figure 6 (C) The Si-O in the spectrum indicates that silica is successfully incorporated into the composite coating, and the roughness provided gives the composite coating excellent superhydrophobic properties.

[0124] 2.6 AFM images

[0125] Figure 7The surface of the super-hydrophobic coating material AW-0.24 is photographed using an atomic force microscope, which can more intuitively observe the roughness and distribution of the coating surface from a microscopic perspective. Figure 7 (A) is a 3D image of the super-hydrophobic coating material AW-0.24. The coating's surface clearly displays a uniformly distributed roughness. The raised areas are peaks formed by agglomeration of particles, while the concave areas are filled with air, creating a hydrophobic effect. Figure 7 (B) is a 2D image of the superhydrophobic coating material AW-0.24. It can be seen very intuitively that the brighter parts of the coating are peaks formed by particle agglomeration, and the darker parts are valleys formed by fewer particles. It can also be seen that the distribution is relatively uniform.

[0126] 2.7 Acid, alkali and temperature resistance

[0127] When soft ceramic sheets are used for outdoor building decoration, they will be affected by the changes in the natural environment and climate. The present invention simulates the natural environment to treat the super hydrophobic coating material AW-0.24. The coating is soaked in acid and alkali solution. Figure 8 (A) Place the coating in a pH = 5 HCl solution and a 5% wt NaOH solution, soak the coating for 0-12 hours respectively; use high temperature and low temperature environments (at +100 ° C and -20 ° C for 0-10 days), see Figure 8 (B) Observation of coating changes.

[0128] like Figure 8 As shown in Figure 2 (A), it is clear that when alkaline immersion exceeds 6 hours, the static water contact angle of the coating drops below 90°. The alkaline solution directly destroys the coating's internal structure, turning it into a hydrophilic surface. When the coating is acid-immersed for 12 hours, the acid further damages the coating's surface structure and chemical composition, causing the coating to lose its superhydrophobic properties and become hydrophobic. The static water contact angle is above 110°. Therefore, the acid resistance of the superhydrophobic coating material AW-0.24 is much higher than its alkali resistance.

[0129] like Figure 8 As shown in Figure 2 (B), although the water contact angle decreases under high temperature conditions, it remains super-hydrophobic for the first six days, maintaining a surface angle above 150°. This indicates that the super-hydrophobic coating material AW-0.24 has strong high-temperature tolerance. When the coating is exposed to low temperatures, the super-hydrophobic angle remains above 150° for the first four days, demonstrating that the coating has a certain degree of low-temperature tolerance.

[0130] 2.8 Self-cleaning ability

[0131] In the natural environment, exterior wall decoration materials are easily contaminated with dust and other pollutants. Therefore, the self-cleaning performance of the transparent super-hydrophobic coating material AW-0.24 against pollution was studied by simulating natural environmental pollutants with black powder. Figure 9 This is a self-cleaning ability test experiment of the super hydrophobic coating material AW-0.24. Figure 9 In the test experiment (A), a microsyringe is used to squeeze a water droplet down and into contact with the coating surface. The needle is then controlled to move downward. It can be seen that the water droplet has completely contacted the coating surface under the action of the needle force. The needle is then controlled to move upward, and it can be clearly seen that the water droplet is quickly lifted. Figure 9 (B) and Figure 9 In the test experiment (C), when a water droplet falls on a surface with dust, a water ball will be formed to carry away the dust, and eventually a concave mark will be formed on the surface where the water droplet has carried away the dust.

[0132] 2.9 Thermal performance analysis results

[0133] Figure 10 The TG, DTG, and DSC curves of the superhydrophobic coating material AW-0.24 clearly show a significant temperature range around 100°C on the TG / DTG curve, indicating a mass loss change (Δm1) due to ethanol evaporation. DSC absorption peaks are observed at temperatures around 900-1200°C, indicating a phase transition in the copolymer. This indicates the copolymer's excellent thermal stability, demonstrating the great potential of the superhydrophobic coating material AW-0.24 as an outdoor decorative material.

[0134] 2.10 Effects of different coating methods on coatings

[0135] Figure 11 The effects of four different coating processes, spraying, pulling, spin coating, and drop coating, on the coating were compared. Among the four processes, the static water contact angle of the coating prepared by the spraying process was the largest, while that of the drop coating process was the largest. Analysis of the experimental process and test results shows that the pull coating process has the smallest contact angle and a large error due to the slow curing of the coating during the pulling process and its inability to fully adhere. The spray coating process has poor hydrophobicity due to the overly dense spraying, which prevents the coating from forming a uniform and neat peak-valley structure. The spin coating process has the smallest error and is the most stable coating method. The drop coating process has the largest static water contact angle, but its error is large and easily affected by the coating's own fluidity.

[0136] 3 Conclusion

[0137] In this study, a superhydrophobic coating was prepared by adding nano-sized silica particles modified with 1H,1H,2H,2H-perfluorodecyltriethoxysilane to a composite resin and then adding γ-aminopropyltriethoxysilane. By controlling the amount of nano-sized silica particles, roughness, and particle size, the optimal roughness and hydrophobicity were determined. The introduction of CNC and EP enhanced the coating's ultimate crack resistance and structural stability.

[0138] The results are as follows:

[0139] (1) The optimal process conditions for the superhydrophobic coating material AW-0.24 are: 0.24 g of waterborne acrylic resin (AA), 0.96 g of waterborne polyurethane (WPU), 0.3 g of FAS-17 modified silica (SiO2), 60 μL of γ-aminopropyltriethoxysilane (KH550), 10 μL of cellulose nanocrystals (CNC), and 10 μL of waterborne epoxy resin (EP). The static water contact angle reaches 162.689°.

[0140] (2) The results of scanning electron microscopy, particle size and Zeta potential performance tests show that the superhydrophobic coating material AW-0.24 forms an uneven, uniform and neat morphology structure;

[0141] (3) XPS spectra show that when FAS-17 modified SiO2 is added to the composite resin, the low surface energy F provides a good chemical basis for the superhydrophobicity of the coating, and combined with the roughness provided by the SiO2 particles, the coating has excellent superhydrophobic properties.

[0142] (4) The results of temperature resistance and corrosion resistance show that the super hydrophobic coating material AW-0.24 has good high and low temperature resistance, acid corrosion resistance, and alkali corrosion resistance still needs to be further improved; the self-cleaning results show that the super hydrophobic coating material AW-0.24 has good self-cleaning properties;

[0143] It can be seen from the TG, DTG and DSC curves of the super-hydrophobic coating material AW-0.24 that it has good thermal stability, indicating that the super-hydrophobic coating material AW-0.24 has a wider application prospect as an outdoor decorative material coating.

Claims

1. A method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material, characterized in that: The following steps are involved: (1) Place the glass slide in a beaker of anhydrous ethanol for ultrasonic cleaning, and then place the cleaned glass slide in an oven for drying. (2) Place the silica particles in a beaker, add anhydrous ethanol to the beaker, stir, and disperse them evenly in an ultrasonic vibration cleaning machine. Then, drop FAS-17 into the beaker, place it in a water bath and stir until all the anhydrous ethanol evaporates. Cool it to obtain the modified silica for use. (3) Add acrylic resin, polyurethane and anhydrous ethanol to a beaker, and then stir in a water bath. Add the modified silica to the beaker, and then stir in a water bath. Then, add γ-aminopropyltriethoxysilane, cellulose nanocrystals and epoxy resin, and then stir in a water bath and cool to room temperature. (4) The coating is applied on a glass slide by coating, and after curing at room temperature, a high-performance water-based acrylic-based soft ceramic super-hydrophobic coating material is obtained.

2. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein In step (1), the glass slide is placed in a beaker containing anhydrous ethanol and ultrasonically cleaned for 10-15 minutes.

3. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein After stirring for 15 minutes in step (2), place it in an ultrasonic vibration cleaning machine.

4. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein After stirring in step (2), the mixture is placed in an ultrasonic vibration cleaning machine and dispersed for 10-15 minutes to ensure uniform dispersion.

5. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein In step (3), acrylic resin, polyurethane and anhydrous ethanol were added to a beaker and stirred in a water bath at 35-40°C for 1 hour.

6. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein In step (3), the modified silica was added to a beaker and stirred in a water bath at 35-40°C for 30 minutes.

7. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein: In step (3), γ-aminopropyltriethoxysilane, cellulose nanocrystals and epoxy resin are added thereto, stirred in a water bath at 35-40° C. for 30-35 minutes and then cooled to room temperature.

8. The method for preparing a high-performance water-based acrylic acid-based soft ceramic super-hydrophobic coating material according to claim 1, wherein: The curing time at room temperature in step (4) is 10-15 minutes.

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