Fluorine-silicon modified super self-cleaning nano coating, preparation method and application thereof

Abstract

The present application relates to the field of paint technology, in particular to a fluorosilicon modified super self-cleaning nano paint, a preparation method and application thereof.The paint is prepared from 25-40 parts of fluorosilicon modified nano silicon dioxide dispersion liquid, 1-3 parts of fluorosilicon modified acrylic resin, 1-3 parts of hydrophilic resin, 0.1-2 parts of silane coupling agent and 50-70 parts of solvent system.The super hydrophobic coating prepared by using the paint is tested by a steel wool friction tester, the load is 100g, and the hydrophobic angle is still above 150° after 1300 times of friction;the water impact resistance is tested by using a 1.2m high, 300mL water flow impact test, and the coating can resist water impact for more than 30 times;the light transmittance of the coating reaches 75%.Moreover, the construction method only needs single layer spraying, and the construction is simple.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to a fluorosilicone modified super self-cleaning nano-coating and its preparation method. Background Technology

[0002] For buildings, industrial facilities, power cables, and vehicles operating in environments with high levels of dust and other contaminants, regular cleaning and maintenance are essential. This is not only for aesthetic reasons but also, and more importantly, for technical maintenance. Excessive dust and contaminant buildup on surfaces can lead to increased energy loss and breakage due to increased weight, and dust entering the equipment can cause short circuits, increased wear, and component damage. However, frequent cleaning and maintenance can also significantly impact normal production and operation. Furthermore, with rising labor costs and the price of cleaning materials, such as water, the expenses associated with various cleaning and maintenance tasks are increasingly becoming a burden on relevant departments.

[0003] Based on the above problems, developing a self-cleaning material that can keep the surfaces of buildings, industrial facilities, power cables, and vehicles clean and shiny for a relatively long time is a suitable solution. Superhydrophobic surface coating materials, originating from the "lotus effect" in nature, are the best answer to these problems. Dust and stains on superhydrophobic surfaces do not penetrate into the inner layer and can be removed with only a very small amount of water, keeping the surface clean and stain-free for a long time.

[0004] However, due to the special rough surface structure required to achieve superhydrophobic surfaces, existing superhydrophobic coatings generally have low strength and poor adhesion to the substrate. With prolonged exposure, the coating is prone to peeling off from the substrate under the erosion of wind, dust, or rain. In addition, existing technologies have relatively complex construction requirements, making them difficult to apply in practice.

[0005] CN1778749A discloses a hydrophobic coating solution based on long-chain alkylsilane coupling agents and alkyl silicate esters, which utilizes small-molecule silane monomers to react on the substrate surface to form a hydrophobic coating. Although the coating can be cured at room temperature, the coating formed by small molecules under these conditions in a short time has low mechanical strength, is easily damaged, is difficult to use for routine quick maintenance, and cannot guarantee sufficient durability.

[0006] CN116218334A discloses a superhydrophobic coating with a shell-like structure and its preparation method. The coating is constructed by mimicking the "brick-and-mortar" structure of nacreous shell layers, with resin binder and hydrophobic particles applied separately in layers to create a multi-layer structure. The increased thickness achieves the wear resistance of the superhydrophobic coating. According to the specification in this document, this coating requires multiple layers of spraying, making large-area application very time-consuming and labor-intensive. Furthermore, because the upper resin layer covers the lower hydrophobic particle layer, the thickness and drying time of both layers need to be precisely controlled to ensure superhydrophobicity, making practical application difficult.

[0007] CN116179047A discloses a wear-resistant superhydrophobic nanocomposite coating and its preparation method, using hydrophobic resin as a binder and micro / nano-structured particles and nanoparticles as fillers. The hydrophobic resin is first cured on the filler surface, and then combined with a resin binder to form a coating. Although the specification states that its production cost is low, the use of larger-diameter particles as hydrophobic particles results in lower dustproof and water impact resistance performance of the coating, leading to poor performance in outdoor applications. Summary of the Invention

[0008] To address the problems of poor wear resistance, short service life, and complex construction process of superhydrophobic coatings, this invention provides a fluorosilicone modified super self-cleaning nano-coating with a strong coating and simple construction, as well as its preparation method and application.

[0009] To address the aforementioned technical problems, this application provides the following technical solution:

[0010] A method for preparing a fluorosilicone modified super self-cleaning nano-coating specifically comprises: 25-40 parts of fluorosilicone modified nano-silica dispersion, 1-3 parts of fluorosilicone modified acrylic resin, 1-3 parts of hydrophilic resin, 0.1-2 parts of silane coupling agent, and 50-70 parts of solvent system.

[0011] The fluorosilicone modified nano-silica is prepared from 1-5 parts of nano-silica, 0.1-2 parts of fluorine-containing long-chain alkylalkoxysilane, 0.05-0.1 parts of γ-aminopropyltriethoxysilane, 0.005-0.02 parts of ammonia water, and 85-95 parts of anhydrous ethanol.

[0012] The nano-silica is hydrophilic nano-silica with a native particle size of 7-50 nm. More preferably, the native particle size of the nano-silica is 7-12 nm.

[0013] The fluorinated long-chain alkylalkoxysilane is tridecylfluorooctyltriethoxysilane or heptadecafluorodecyltriethoxysilane.

[0014] The fluorosilicone modified acrylic resin is mainly prepared from 20-40 parts butyl acrylate, 0.5-1.5 parts methacrylic acid, 10-15 parts methyl methacrylate, 3-6 parts dodecafluoroheptyl methacrylate, 1-3 parts γ-(methacryloyloxy)propyltrimethoxysilane, 0.1-0.6 parts hydroxyethyl acrylate, 0.3-0.5 parts benzoyl peroxide, and 30-50 parts butyl acetate.

[0015] The hydrophilic resin is polyvinylpyrrolidone or hydroxypropyl cellulose.

[0016] The silane coupling agent includes at least one of γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-glycidoxypropyltriethoxysilane.

[0017] The solvent system includes one or more of propylene glycol methyl ether, dipropylene glycol methyl ether, diethylene glycol butyl ether, butanol, and anhydrous ethanol.

[0018] The fluorosilicone modified super self-cleaning nano-coating prepared by the method of this invention can be used to make superhydrophobic coatings on buildings, industrial facilities, power cables, vehicles and heavy equipment.

[0019] Compared with the prior art, the fluorosilicone modified super self-cleaning nano-coating of the present invention, its preparation method and application have at least the following advantages:

[0020] Beneficial effects:

[0021] In the fluorosilicone-modified super-self-cleaning nano-coating of this invention, fluorosilicone modification of nano-silica is performed, grafting long-chain fluorosilicone structures onto the surface of nano-silica to generate hydrophobic nano-silica with low surface energy. Using acrylic resin as the main body, fluorosilicone groups are introduced, improving the compatibility between the resin and the hydrophobic nano-silica and resulting in better transparency after curing of the superhydrophobic coating. By adding a hydrophilic resin to the superhydrophobic coating, which is incorporated as a dispersed phase into the superhydrophobic coating system, the superhydrophobic coating becomes denser and possesses higher mechanical strength. When the outer hydrophobic structure is damaged, the inner hydrophobic structure can continue to function, giving the superhydrophobic coating self-healing properties. The use of a silane coupling agent improves the density and wear resistance of the superhydrophobic coating.

[0022] The superhydrophobic coating prepared using the coating of this invention was tested for abrasion resistance using a steel wool abrasion tester. Under a load of 100g, the hydrophobic angle remained above 150° after 1300 abrasion cycles. It withstood more than 30 water impacts from a height of 1.2 meters and a flow of 300mL. The coating's light transmittance reached 75%. Furthermore, the application method requires only a single layer of spraying, making construction simple.

[0023] The following provides a further explanation of the fluorosilicone modified ultra-self-cleaning nano-coating of the present invention, its preparation method, and its application. Detailed Implementation

[0024] Example 1

[0025] A method for preparing a fluorosilicone-modified super self-cleaning nano-coating, comprising the following steps:

[0026] (1) Preparation of fluorosilicone modified nano-silica dispersion

[0027] By mass, 94.45 parts of anhydrous ethanol and 5 parts of nano-silica were added to the reactor and stirred at 3000 r / min for 1 h. Then, 0.5 parts of tridecafluorooctyltriethoxysilane were added, the reaction temperature was set to 60℃, 0.01 parts of ammonia water were added, and the reaction was stirred for another 1.5 h. Then, 0.05 parts of γ-aminopropyltriethoxysilane were added, and the reaction was stirred for another 1 h. After the reaction was completed, the mixture was cooled and removed to obtain an anhydrous ethanol dispersion of fluorosilicone-modified nano-silica.

[0028] Among them, the nano-silica is hydrophilic nano-silica with a native particle size of 7nm.

[0029] (2) Preparation of fluorosilicone modified acrylic resin

[0030] By weight, 40 parts of butyl acetate were added to the reactor, and the temperature was raised to 110°C. 30 parts of butyl acrylate, 1 part of methacrylic acid, 12 parts of methyl methacrylate, 0.4 parts of hydroxyethyl acrylate, 4 parts of dodecafluoroheptyl methacrylate, 2 parts of γ-(methacryloyloxy)propyltrimethoxysilane, and 0.4 parts of benzoyl peroxide were pre-mixed and added dropwise to the reaction system over 2.5 hours. After the addition was complete, the reaction temperature was adjusted to reflux and maintained at reflux temperature for 2 hours. 10 parts of butyl acetate and 0.2 parts of benzoyl peroxide were pre-mixed and added dropwise to the reactor over 1.5 hours at a uniform rate. When the conversion rate reached over 95%, the mixture was cooled and discharged to obtain the fluorosilicone-modified acrylic resin.

[0031] (3) Preparation of superhydrophobic coatings

[0032] By weight, 2 parts of polyvinylpyrrolidone and 18 parts of ethanol were mixed evenly to prepare a polyvinylpyrrolidone ethanol solution. 35 parts of the fluorosilicone-modified nano-silica ethanol dispersion prepared in step (1) and 2 parts of the fluorosilicone-modified acrylic resin prepared in step (2) were added to the polyvinylpyrrolidone ethanol solution and mixed and stirred. Then, 18 parts of propylene glycol methyl ether, 44 parts of anhydrous ethanol, 0.5 parts of γ-aminopropyltriethoxysilane and 0.5 parts of γ-glycidoxypropyltrimethoxysilane were added and stirred evenly to form a superhydrophobic coating.

[0033] The above-mentioned superhydrophobic coating is sprayed onto a glass slide and allowed to dry naturally for 24 hours to form a superhydrophobic coating.

[0034] Example 2

[0035] A method for preparing a fluorosilicone-modified super self-cleaning nano-coating, comprising the following steps:

[0036] (1) Preparation of fluorosilicone modified nano-silica dispersion

[0037] By mass, 94 parts of anhydrous ethanol and 5 parts of nano-silica were added to the reaction vessel and stirred at 3000 r / min for 1 h. Then, 0.94 parts of heptadecafluorodecyltriethoxysilane were added, the reaction temperature was set to 60℃, 0.01 parts of ammonia water were added, and the reaction was stirred for another 1.5 h. Then, 0.05 parts of γ-aminopropyltriethoxysilane were added, and the reaction was stirred for another 1 h. After the reaction was completed, the mixture was cooled and removed to obtain an anhydrous ethanol dispersion of fluorosilicone-modified nano-silica.

[0038] Among them, the nano-silica is hydrophilic nano-silica with a native particle size of 12nm.

[0039] The remaining steps are the same as steps (2) and (3) in Example 1.

[0040] Example 3

[0041] A method for preparing a fluorosilicone-modified super self-cleaning nano-coating, comprising the following steps:

[0042] (1) Same as step (1) in Example 1.

[0043] (2) By weight, 40 parts of butyl acetate were added to the reactor, and then the temperature was raised to 110°C. 29 parts of butyl acrylate, 1 part of methacrylic acid, 10 parts of methyl methacrylate, 0.4 parts of hydroxyethyl acrylate, 6 parts of dodecafluoroheptyl methacrylate, 3 parts of γ-(methacryloyloxy)propyltrimethoxysilane, and 0.4 parts of benzoyl peroxide were pre-mixed and added dropwise to the reaction system over 2.5 hours. After the addition was complete, the reaction temperature was adjusted to reflux and maintained at reflux temperature for 2 hours. 10 parts of butyl acetate and 0.2 parts of benzoyl peroxide were pre-mixed and then added dropwise to the reactor over 1.5 hours at a uniform rate. When the conversion rate reached over 95%, the mixture was cooled and discharged to obtain the fluorosilicone modified acrylic resin.

[0044] (3) Same as step (3) in Example 1.

[0045] Example 4

[0046] A method for preparing a fluorosilicone-modified super self-cleaning nano-coating, comprising the following steps:

[0047] (1) Same as step (1) in Example 1.

[0048] (2) Same as step (2) in Example 1.

[0049] (3) By mass, 2 parts of hydroxypropyl cellulose and 18 parts of ethanol are mixed evenly to prepare an ethanol solution of polyvinylpyrrolidone. 35 parts of the fluorosilicone-modified nano-silica ethanol dispersion prepared in step (1) and 2 parts of the fluorosilicone-modified acrylic resin prepared in step (2) are added to the polyvinylpyrrolidone ethanol solution and mixed and stirred. Then, 18 parts of propylene glycol methyl ether, 44 parts of anhydrous ethanol, 0.5 parts of γ-aminopropyltriethoxysilane and 0.5 parts of γ-glycidoxypropyltrimethoxysilane are added and stirred evenly to form a superhydrophobic coating.

[0050] To highlight the beneficial effects of the present invention, the following comparative examples are provided.

[0051] Comparative Example 1

[0052] This comparative example is used to describe the performance difference when commercially available pure acrylic acid is used instead of the fluorosilicone-modified acrylic acid of this invention.

[0053] By weight, 2 parts of polyvinylpyrrolidone and 18 parts of ethanol were mixed evenly to prepare a polyvinylpyrrolidone ethanol solution. 35 parts of the fluorosilicone-modified nano-silica ethanol dispersion prepared in step (1) of Example 1 and 2 parts of commercially available pure acrylic resin were added to the polyvinylpyrrolidone ethanol solution and mixed and stirred. Then, 18 parts of propylene glycol methyl ether, 24 parts of anhydrous ethanol, 0.5 parts of γ-aminopropyltriethoxysilane and 0.5 parts of γ-glycidoxypropyltrimethoxysilane were added and stirred evenly to form a superhydrophobic coating.

[0054] The above-mentioned superhydrophobic coating is sprayed onto a glass slide and allowed to dry naturally for 24 hours to form a superhydrophobic coating.

[0055] Comparative Example 2

[0056] This comparative example is used to describe the performance differences without the addition of hydrophilic resin.

[0057] By weight, 35 parts of the fluorosilicone modified nano-silica ethanol dispersion prepared in step (1) of Example 1 and 2 parts of the fluorosilicone modified acrylic resin prepared in step (2) of Example 1 were mixed and stirred evenly. Then, 18 parts of propylene glycol methyl ether, 44 parts of anhydrous ethanol, 0.5 parts of γ-aminopropyltriethoxysilane and 0.5 parts of γ-glycidoxypropyltrimethoxysilane were added and stirred evenly to form a superhydrophobic coating.

[0058] The above-mentioned superhydrophobic coating is sprayed onto a glass slide and allowed to dry naturally for 24 hours to form a superhydrophobic coating.

[0059] Comparative Example 3

[0060] This comparative example is used to describe the performance differences with different addition amounts of silane coupling agents.

[0061] By mass, 2 parts of polyvinylpyrrolidone are mixed evenly with 18 parts of ethanol to prepare an ethanol solution of polyvinylpyrrolidone. 35 parts of the fluorosilicon-modified nano-silica ethanol dispersion prepared in step (1) of Example 1 and 2 parts of the fluorosilicon-modified acrylic resin prepared in step (2) of Example 1 are added to the polyvinylpyrrolidone ethanol solution, mixed and stirred, then 18.5 parts of propylene glycol methyl ether, 44 parts of absolute ethanol and 0.5 part of γ-glycidoxypropyltrimethoxysilane are added and stirred evenly to form a superhydrophobic coating.

[0062] The above superhydrophobic coating is sprayed onto a glass sheet and dried naturally for 24 h to form a superhydrophobic coating.

[0063] The abrasion resistance, water flushing resistance and light transmittance of the products of Examples 1-3 and Comparative Examples 1-3 are tested respectively.

[0064] Abrasion resistance test: The test is carried out using a wire wool abrasion tester. 0000# wire wool is used, with an area of 10 mm×10 mm, a stroke of 40 times / min, a load of 100 g. The water contact angle of the test sample is measured every 100 frictions. The test stops when the water contact angle is less than 150°, and the final number of times is recorded.

[0065] Water impact resistance test: 1 mL of red ink is added to 1 L of distilled water or water conforming to GB / T 6682-2008 and stirred well. The red ink is commercially available red ink and conforms to QB / T1745.1-2011. A funnel with a capacity of 300 ml is used, and a plastic tube with a length of 15 cm and an inner diameter of 2 cm is connected below. The test sample is placed 1.2 m below the plastic tube, and the test point is marked on the test sample. 300 ml of test water is poured into the funnel. The test water is allowed to freely fall under the action of gravity to impact the surface of the test point of the test plate. After all 300 ml of water has flowed out, the surface of the test plate is inspected. If there is no color contamination on the surface of the test plate, it is regarded as qualified and the next water impact resistance test can be continued. When the surface of the test plate is contaminated with colored water droplets, the detection stops, and the test plate is placed in an oven and baked at 80 °C for 10 min. Then the test plate is continued to be tested for water impact at the original test point. Such cycles are carried out until the test point is immediately contaminated with colored water droplets under water impact after baking, and the final number of times is recorded.

[0066] Light transmittance test: The test is carried out in accordance with the test standard of GB / T 7106-2008.

[0067] The test results are shown in Table 1 below.

[0068] Table 1

[0069]

[0070] The above results show that the superhydrophobic coating prepared by the method of this invention, when tested with a steel wool abrasion tester, maintains a hydrophobic angle above 150° after 1300 abrasion cycles with a load of 100g. It can withstand more than 30 water impacts from a height of 1.2 meters and a flow of 300mL. The coating's light transmittance reaches 75%. Furthermore, the coating of this invention requires only a single-layer spray application, making construction simple.

[0071] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a fluorosilicone-modified super self-cleaning nano-coating, characterized in that: It is prepared from 25-40 parts of fluorosilicone modified nano-silica dispersion, 1-3 parts of fluorosilicone modified acrylic resin, 1-3 parts of hydrophilic resin, 0.1-2 parts of silane coupling agent and 50-70 parts of solvent system; The fluorosilicone-modified nano-silica dispersion is prepared from 1-5 parts nano-silica, 0.1-2 parts fluorinated long-chain alkylalkoxysilane, 0.05-0.1 parts γ-aminopropyltriethoxysilane, 0.005-0.02 parts ammonia water, and 85-95 parts anhydrous ethanol; the fluorinated long-chain alkylalkoxysilane is tridecafluorooctyltriethoxysilane or heptadecafluorodecyltriethoxysilane; The fluorosilicone modified acrylic resin is prepared from 20-40 parts butyl acrylate, 0.5-1.5 parts methacrylic acid, 10-15 parts methyl methacrylate, 3-6 parts dodecafluoroheptyl methacrylate, 1-3 parts γ-(methacryloyloxy)propyltrimethoxysilane, 0.1-0.6 parts hydroxyethyl acrylate, 0.3-0.5 parts benzoyl peroxide, and 30-50 parts butyl acetate. The hydrophilic resin is polyvinylpyrrolidone or hydroxypropyl cellulose; The silane coupling agent includes at least one of γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-glycidoxypropyltriethoxysilane.

2. The preparation method of the fluorosilicone modified super self-cleaning nano-coating according to claim 1, characterized in that: The nano-silica is hydrophilic nano-silica with a native particle size of 7-50 nm.

3. The preparation method of the fluorosilicone modified super self-cleaning nano-coating according to claim 1, characterized in that: The solvent system is one or more of propylene glycol methyl ether, dipropylene glycol methyl ether, diethylene glycol butyl ether, butanol, and anhydrous ethanol.

4. Fluorosilicone modified super self-cleaning nanocoating prepared by any of the preparation methods described in claims 1-3.

5. The application of the fluorosilicone modified self-cleaning nano-coating according to claim 4 in buildings, industrial facilities, power cables, vehicles and heavy equipment.

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