Double-size wear-resistant super-hydrophobic material based on phase separation method as well as preparation method and application of double-size wear-resistant super-hydrophobic material

Abstract

The invention relates to the field of inorganic materials, in particular to a dual-size wear-resistant super-hydrophobic material based on a phase separation method, which comprises dual-size ethanol-containing semi-solid PF-SiO2 nanoparticles, polyolefin glue and butyl acetate, the dual-size ethanol-containing semi-solid PF-SiO2 nano-particles comprise large-size semi-solid PF-SiO2 nano-particles and small-size semi-solid PF-SiO2 nano-particles, and the preparation method comprises the following steps: uniformly mixing SiO2 nano-particles with an ethanol solution, adding sodium methyl silicate, uniformly stirring, adding PFDTES and tetraethyl orthosilicate, carrying out a mechanical stirring reaction to form a suspension liquid, and drying the suspension liquid to obtain the dual-size ethanol-containing semi-solid PF-SiO2 nano-particles. The preparation method comprises the following steps: preparing a POA / modified SiO2 suspension liquid, adding ethanol into the suspension liquid, centrifuging the suspension liquid to obtain semi-solid PF-SiO2 nano-particles containing ethanol, dissolving polyolefin glue (POA) into butyl acetate, stirring for 20-25 minutes, adding large-size semi-solid PF-SiO2 nano-particles and small-size semi-solid PF-SiO2 nano-particles in a stirring state, and stirring for 3-3.5 hours to obtain the POA / modified SiO2 suspension liquid. By implementing the scheme, the super-hydrophobic material with good hydrophobic performance and high wear resistance is obtained.

Description

Technical Field

[0001] The present invention relates to the field of inorganic materials, and in particular to a dual-size wear-resistant super-hydrophobic material based on a phase separation method, a preparation method and an application thereof. Background Art

[0002] Good mechanical stability is a prerequisite for the practical application of super-hydrophobic surfaces. However, most super-hydrophobic surfaces inherently have poor mechanical stability because wear can easily destroy their layered structure due to mechanical stress concentration. This is the main obstacle limiting its practical application. In order to solve this problem, researchers have made significant progress in improving mechanical stability by using composite wear-resistant materials (CN118027782A), designing self-healing surfaces (CN112724782B), constructing self-similar structures (CN119500522A) and building protective microstructures (CN113604095B). In addition, from the perspective of preparation methods, such as laser etching, template method, electrochemical method, etc., which are subject to instrumentation, the large-scale preparation of super-hydrophobic coatings is limited. Spraying method and dip coating method are not subject to these limitations and can expand the application of super-hydrophobic coatings to more fields.

[0003] CN 108864778 A discloses a super-hydrophobic coating with a micron-nano hierarchical structure composed of dual-sized SiO2 particles and a preparation method thereof. The method comprises adding two SiO2 particles of different sizes to ethanol, mixing them, and then adding organosilane for ultrasonic dispersion to uniformly prepare the super-hydrophobic coating. Although the coating has improved hydrophobicity, it utilizes weak interaction forces between particles and the Ostwald ripening mechanism to achieve stable and tight bonding between large-sized and small-sized SiO2 particles. Therefore, the wear resistance of the coating is not high, and it cannot be used in scenarios with high wear resistance requirements.

[0004] Therefore, it is necessary to develop a super-hydrophobic material with good hydrophobicity and high wear resistance. Summary of the Invention

[0005] One of the purposes of the present invention is to provide a dual-size wear-resistant super-hydrophobic material based on a phase separation method, which can improve both the wear resistance and hydrophobicity of the coating through the coordinated coordination and precise proportion of the components.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a dual-size wear-resistant super-hydrophobic material based on a phase separation method, comprising dual-size ethanol-containing semi-solid PF-SiO2 nanoparticles, polyolefin glue and butyl acetate, wherein the dual-size ethanol-containing semi-solid PF-SiO2 nanoparticles comprise large-size semi-solid PF-SiO2 nanoparticles and small-size semi-solid PF-SiO2 nanoparticles.

[0007] Preferably, as an improvement, the addition ratio of the dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles to the polyolefin glue is 2.4 to 5.0.

[0008] Preferably, as an improvement, the ratio of large-sized semi-solid PF-SiO2 nanoparticles to small-sized semi-solid PF-SiO2 nanoparticles is 5:(2-5).

[0009] Preferably, as an improvement, the particle size of the large-sized semi-solid PF-SiO2 nanoparticles is 100 to 200 nm.

[0010] Preferably, as an improvement, the particle size of the small-sized semi-solid PF-SiO2 nanoparticles is 10 to 20 nm.

[0011] The second purpose of the present invention is to provide a method for preparing a dual-sized wear-resistant superhydrophobic material based on a phase separation method. By implementing this method, PF-SiO2 nanoparticles are tightly wrapped on the surface of POA microspheres, forming a dense but rough surface at the nanoscale, and its surface produces a self-similar structure at the micron and nanometer levels, thereby significantly improving the hydrophobicity and wear resistance of the superhydrophobic coating.

[0012] A method for preparing a dual-size wear-resistant super-hydrophobic material based on a phase separation method comprises the following steps:

[0013] S1. Synthesis of dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles. Two SiO2 nanoparticles of different particle sizes are synthesized separately. The synthesis steps are as follows: after uniformly mixing the SiO2 nanoparticles with an ethanol solution, sodium methyl silicate is added and stirred evenly, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (PFDTES) and tetraethyl orthosilicate are added and mechanically stirred to react to form a suspension, and the suspension is centrifuged to obtain semi-solid PF-SiO2 nanoparticles containing ethanol;

[0014] S2. Dissolve polyolefin glue (POA) in butyl acetate, stir for 20-25 minutes, add large-sized semi-solid PF-SiO2 nanoparticles and small-sized semi-solid PF-SiO2 nanoparticles under stirring, and stir for 3-3.5 hours to obtain a POA / modified SiO2 suspension.

[0015] Preferably, as an improvement, in step S1, the addition ratio of SiO2 nanoparticles to ethanol solution is 1g: (65-75)ml; the ethanol solution comprises 23 parts of ethanol and 2 parts of water.

[0016] Preferably, as an improvement, in step S1, the mass ratio of SiO2 nanoparticles: sodium methyl silicate: PFDTES: tetraethyl orthosilicate is 1:0.3:(1.63-1.67):0.28. The mass ratio herein refers to the effective mass added. For example, if 1 g of sodium methyl silicate is added but the solid content of sodium methyl silicate is 30%, the mass ratio is 0.3.

[0017] Preferably, as an improvement, in step S1, the SiO2 nanoparticles are mixed with the ethanol solution by mechanical stirring for 15 minutes and ultrasonic treatment for 15 minutes.

[0018] A dual-size wear-resistant super-hydrophobic material based on a phase separation method is applied to the coating field. When used, the dual-size wear-resistant super-hydrophobic material is sprayed onto a substrate with a spray gun and cured at room temperature for 24 hours to obtain a phase-separated super-hydrophobic coating.

[0019] The principle and advantages of this scheme are

[0020] 1. In order to improve the wear resistance of the coating, this solution has developed a solution that is completely opposite to the traditional solution: the traditional method is to modify a layer of decorative layer on the surface of SiO2, the purpose of which is to delay the grinding time of SiO2. During the grinding process, the first thing to be worn off is the decorative layer on the surface. Only after the decorative layer is worn off will the SiO2 below be worn off. When SiO2 is gradually worn off, the superhydrophobicity is gradually lost. Although this method can extend the friction cycle of the coating to a certain extent, its own wear resistance is not good. This solution is an opposite idea. Through a special preparation process, PF-SiO2 is wrapped on the surface of POA. Since PF-SiO2 itself is wear-resistant and has a circular structure, it is not easy to be worn off. Even if a part of PF-SiO2 is worn off during the friction process, PF-SiO2 in other places will be continuously replenished when it is ground again. This process greatly improves the wear resistance of the coating.

[0021] 2. Compared with the structure of SiO2 embedded in the adhesive formed by the traditional blending spraying method, this method adds semi-solid double-sized nano-scale SiO2 containing ethanol to the polyolefin / butyl acetate solution. During the stirring and curing process, due to the different boiling points of ethanol and butyl acetate, the ethanol evaporates faster than butyl acetate, and phase separation occurs. The POA microspheres partially dissolve and connect to each other, thereby causing the aggregation of the POA microspheres. In addition, due to the volatilization of the organic solvent and the adhesion between the organic solvent and the inorganic nanoparticles, the PF-SiO2 nanoparticles are tightly wrapped on the surface of the POA microspheres, forming a dense but rough surface at the nanoscale, significantly improving the hydrophobicity of the superhydrophobic coating, making the coating contact angle as high as 160.6±1.0° and the sliding angle as low as 2.7±0.4°. At the same time, this case uses a special preparation process, and phase separation occurs during the preparation process, and its surface produces a self-similar structure at the micron and nanometer levels. Once the coating surface is destroyed, the exposed new surface still has almost the same performance as the original surface, thereby further significantly improving the wear resistance of the coating.

[0022] 3. This scheme prepares dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles, accurately controls the ratio of them to POA, and accurately controls the addition ratio between large-sized semi-solid PF-SiO2 nanoparticles and small-sized semi-solid PF-SiO2 nanoparticles, so that the POA-based wear-resistant superhydrophobic coating exhibits excellent wear resistance and hydrophobic properties.

[0023] 4. This solution uses low-cost raw materials and does not rely on expensive instruments and equipment and complex processes. It has the advantages of simple operation and easy large-scale production, providing an economically feasible technical path for the industrial preparation of wear-resistant superhydrophobic coatings.

[0024] 5. The coating made of this dual-size wear-resistant super-hydrophobic material has self-cleaning and anti-fouling properties.

[0025] 6. The super-hydrophobic coating made of this dual-size wear-resistant super-hydrophobic material has high-temperature stability and still has super-hydrophobicity after being placed at a high temperature of 120-140°C for 4 hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The water contact angle curves of the coatings with different ratios of double-sized semi-solid PF-SiO2 nanoparticles containing ethanol and POA after abrasion.

[0027] Figure 2 The water contact angle curves of coatings with different ratios of large / small-sized semi-solid PF-SiO2 nanoparticles and POA after wear are shown in Figure 2.

[0028] Figure 3These are SEM images of the super-hydrophobic coating at different magnifications.

[0029] Figure 4 Adhesion evaluation test diagram of the super-hydrophobic coating ABS plate (a) and magnesium alloy substrate (b).

[0030] Figure 5 Schematic diagram of the contact angle of the superhydrophobic coating after immersion in 1M HCl (a) and 3.5wt% NaCl (b) solutions for 24h.

[0031] Figure 6 This is the contact angle change diagram of the super-hydrophobic coating before and after high temperature testing.

[0032] Figure 7 Schematic diagram of the hydrophobicity of the super-hydrophobic coating prepared on different substrates and the hydrophobicity of various solutions.

[0033] Figure 8 Schematic diagram of the self-cleaning and anti-fouling performance test of the superhydrophobic coating. DETAILED DESCRIPTION

[0034] A dual-sized wear-resistant super-hydrophobic material based on a phase separation method includes dual-sized semi-solid PF-SiO2 nanoparticles containing ethanol, polyolefin glue (POA) and butyl acetate. The addition ratio of the dual-sized semi-solid PF-SiO2 nanoparticles containing ethanol to the polyolefin glue is 2.4-5.0, and the optimal addition ratio is controlled at 3.0-4.0. The amount of butyl acetate added is 3-6 times that of the dual-sized semi-solid PF-SiO2 nanoparticles containing ethanol. If there is too little butyl acetate, the suspension is too thick and cannot be sprayed; if there is too much butyl acetate, there is too much solvent, which may cause the coating to crack.

[0035] The dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles include large-sized semi-solid PF-SiO2 nanoparticles and small-sized semi-solid PF-SiO2 nanoparticles. The large-sized semi-solid PF-SiO2 nanoparticles have a particle size of 100 to 200 nm. In this embodiment, a particle size of 100 nm is used as an example, and hereinafter referred to as PF-SiO2 (100 nm). The small-sized semi-solid PF-SiO2 nanoparticles have a particle size of 10 to 20 nm. In this embodiment, a particle size of 12 nm is used as an example, and hereinafter referred to as PF-SiO2 (12 nm). The ratio of PF-SiO2 (100 nm) to PF-SiO2 (12 nm) is 5:2, 5:3, 5:4, or 5:5.

[0036] Among them, the double-sized semi-solid PF-SiO2 nanoparticles containing ethanol: POA = 3.0 ~ 4.0, and PF-SiO2 (100nm) / PF-SiO2 (12nm) = 5:4, the contact angle and wear resistance of the superhydrophobic coating can reach the best state.

[0037] The preparation method of the dual-size wear-resistant superhydrophobic material based on the phase separation method is as follows:

[0038] S1. Synthesis of Dual-Sized Semi-Solid PF-SiO2 Nanoparticles Containing Ethanol

[0039] First, 100nm and 12nm SiO2 nanoparticles were synthesized separately. Taking PF-SiO2 (100nm) as an example, the synthesis steps were as follows: 1g of SiO2 (100nm) nanoparticles was dispersed in 70mL of ethanol solution (ethanol / water: 23 / 2). Then, after mechanical stirring for 15 minutes and ultrasonic treatment for 15 minutes, 1g of sodium methyl silicate was added and stirred continuously for 15 minutes. Then, 1.2mL of 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) and 0.3mL of tetraethyl orthosilicate (TEOS) were added and mechanically stirred for 2 hours under room temperature to form a suspension. The suspension was then centrifuged to obtain semi-solid PF-SiO2 (100nm) nanoparticles containing ethanol.

[0040] Semi-solid PF-SiO2 (12 nm) nanoparticles containing ethanol were prepared according to the above synthesis steps.

[0041] S2. Preparation of POA-based superhydrophobic coating

[0042] First, 1.4 g of polyolefin adhesive (POA) was dissolved in 15.0 g of butyl acetate and mechanically stirred for 20 minutes. Subsequently, 3.5 g of PF-SiO2 (100 nm) nanoparticles were slowly added under stirring. Subsequently, PF-SiO2 (12 nm) nanoparticles were added in ratios of PF-SiO2 (100 nm) / PF-SiO2 (12 nm) of 5:2, 5:3, 5:4, and 5:5, respectively. The POA gradually phase-separated during this process. Further stirring for 3 hours yielded a uniform POA / modified SiO2 suspension.

[0043] The POA / modified SiO2 suspension prepared above was sprayed onto an ABS plate using a 0.2 MPa spray gun and cured at room temperature for 24 h to produce a phase-separated superhydrophobic coating. Coatings on other substrates were prepared using the same process.

[0044] experiment

[0045] 1. Determine the ratio between dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles and polyolefin glue

[0046] Among them, the double-sized semi-solid PF-SiO2 nanoparticles containing ethanol are PF-SiO2 (100nm) / PF-SiO2 (12

[0047] nm)=5:2 as an example to conduct the experiment, the details are as follows:

[0048] <![CDATA[PF-SiO2 / POA ratio]]> Contact angle 1 / ° Contact angle 2 / ° Contact angle 3 / ° Average contact angle / ° Standard deviation / ° 0.5 85.3 85.2 83.8 84.8 0.8 1 106.8 107.8 106.5 107.0 0.7 2 125.7 125.2 125.7 125.5 0.3 2.5 154.3 154.1 154.5 154.3 0.2 3.5 157.0 158.2 157.1 157.4 0.7 4.5 156.0 155.7 155.8 155.8 0.2 5.0 154.5 154.5 154.8 154.6 0.2 6.0 153.3 154.7 153.9 153.9 0.5

[0049] Table 1

[0050] 1. Hydrophobicity test results

[0051] As shown in Table 1, when PF-SiO2 / POA ≤ 2, the prepared coating is not a superhydrophobic coating. When PF-SiO2 / POA = 3.5, the contact angle of the coating is 157.4 ± 0.7°. When PF-SiO2 / POA = 5.0, the contact angle of the coating is 154.6 ± 0.2°, which is the highest contact angle of the coating. When PF-SiO2 / POA = 6.0, the contact angle of the coating is 153.9 ± 0.5°.

[0052] In summary, when PF-SiO2 / POA>2, the prepared coating is a superhydrophobic coating, but as the PF-SiO2 / POA ratio increases, the contact angle tends to decrease.

[0053] 2. Wear resistance test results

[0054] Take the three samples with PF-SiO2 / POA=3.5, 5.0 and 6.0 on ABS coating as an example, use 100g weight and 1000-grit sandpaper, perform 5 friction cycles and measure the contact angle of the coating, as shown in the following figure: Figure 1 shown.

[0055] For the coating with PF-SiO2 / POA=3.5, after 25 wear cycles, the average contact angle of the coating is 148.6°, which is less than 150°. After that, within 25 to 50 friction cycles, as the number of wear cycles increases, the average contact angle of the coating remains at 147.3 to 149.7° ( Figure 1 (b)).

[0056] For the coating with PF-SiO2 / POA=5.0, after 30 wear cycles, the average contact angle of the coating is less than 150°. After that, as the number of wear cycles increases, the average contact angle of the coating is greater than 150° again. After the 50th friction cycle, the average contact angle reaches 146.5°, which still has a certain degree of hydrophobicity ( Figure 1 (c)).

[0057] For the coating with PF-SiO2 / POA=6.0, the average contact angle of the coating is less than 150° after 15 wear cycles. After the 20th wear cycle, the average contact angle of the coating is again greater than 150°. Thereafter, within 25-50 friction cycles, as the number of wear cycles increases, the average contact angle of the coating remains between 142.5° and 148.9° ( Figure 1 (d)).

[0058] In summary, compared with the three coatings of PF-SiO2 / POA=3.5, 5.0, and 6.0, the wear resistance of PF-SiO2 / POA=3.5 and 5.0 is not much different. After 50 friction cycles, the contact angles are 149.7±0.7° and 146.5±2.4°, respectively. However, the wear resistance of PF-SiO2 / POA=6.0 is weaker, and after 50 friction cycles, the average contact angle of the coating is 142.5±0.7°. In summary, as the PF-SiO2 / POA ratio increases, the wear resistance of the superhydrophobic coating gradually weakens due to the decrease in the relative content of POA.

[0059] 2. Determine the ratio of PF-SiO2 (100nm) and PF-SiO2 (12nm)

[0060] After determining the appropriate ratio of PF-SiO2 to POA, we tested the ratios of PF-SiO2 (100 nm) and PF-SiO2 (12 nm) using the two ratios of PF-SiO2 / POA = 3.5 and 5.0 in Experiment 1 to achieve optimal hydrophobicity and wear resistance. See Tables 2 and 3 for details.

[0061] The number of wear times refers to the number of frictions the coating undergoes before the contact angle fails. The contact angle failure criterion is: after several frictions, the contact angle drops by more than 10%, which is considered to be a failure.

[0062]

[0063]

[0064] Table 2 PF-SiO2 / POA=3.5 dual-size super-hydrophobic coating contact angle data

[0065]

[0066] Table 3 PF-SiO2 / POA=5.0 dual-size super-hydrophobic coating contact angle data

[0067] 2.1 Hydrophobicity test results

[0068] As shown in Table 2, when the addition ratio of SiO2 (12 nm) gradually increases, the contact angle of the coating also increases. When the ratio of SiO2 (100 nm): SiO2 (12 nm) in the superhydrophobic coating is 5:4, the contact angle of the coating is the highest, which is 160.2±1.5°. However, when the addition ratio of the two is less than 5:4, the contact angle of the coating shows a downward trend.

[0069] As shown in Table 3, when the SiO2 (100 nm):SiO2 (12 nm) ratio is 5:1, the contact angle of the coating is not as good as that of the single-size coating. When the ratio is less than 5:1, the wear resistance of the coating is significantly improved. Furthermore, when the SiO2 (100 nm):SiO2 (12 nm) ratio in the superhydrophobic coating is 5:4, the coating's contact angle is the highest, at 155.9 ± 0.9°. However, when the ratio is less than 5:4, the coating's contact angle begins to decrease.

[0070] 2.2 Wear resistance test results

[0071] Using a 100 g weight and 1000 grit sandpaper, the contact angle of the coating was measured after every 5 friction cycles. The wear resistance of the two coatings was tested. The test results are shown in Tables 2 and 3.

[0072] It can be seen from Tables 2 and 3 that the ratio between SiO2 (100nm) and SiO2 (12nm) is very critical to the wear resistance of the coating. When the ratio between the two is 5:1, its wear resistance is not as good as that of a single size. When the ratio is less than 5:1, and with the increase of SiO2 (12nm), the wear resistance of the coating is significantly improved; but when the ratio between the two is less than 5:4, the wear resistance of the coating begins to decline, and the contact angle also begins to decline.

[0073] Among them, when the SiO2 (100nm): SiO2 (12nm) in the coating is 5:4, its hydrophobicity and wear resistance reach the optimal state.

[0074] When the ratio of SiO2 (100 nm): SiO2 (12 nm) in PF-SiO2 (total) is 5:4, the two coatings with the ratio of PF-SiO2 (total): POA being 3.5 and 5.0, respectively, were named PF-SiO2 (5:4) / POA=3.5 and PF-SiO2 (5:4) / POA=5.0, respectively.

[0075] Figure 2 Specifically demonstrated are the wear resistance of two coatings: PF-SiO2(5:4) / POA=3.5 and PF-SiO2(5:4) / POA=5.0:

[0076] After the 40th wear cycle, the average contact angle of the PF-SiO2 (5:4) / POA = 3.5 coating was less than 150°, and after 60 wear cycles, it could still maintain a high contact angle (149.1 ± 0.3°), proving that the superhydrophobic coating still has good wear resistance.

[0077] The average contact angle of the PF-SiO2 (5:4) / POA = 5.0 coating was less than 150° after 15 sandpaper abrasion cycles, and the contact angle was 134.4 ± 1.2° after 60 abrasion cycles.

[0078] This also shows that as the content of PF-SiO2 particles increases, the hydrophobicity of the coating will not necessarily increase, but the wear resistance of the coating will gradually weaken.

[0079] In summary, when PF-SiO2 / POA is 3.5 and PF-SiO2 (100nm):PF-SiO2 (12nm) = 5:4, the contact angle of the coating is the highest and the wear resistance is the best.

[0080] Figure 3 The scanning electron microscope analysis diagrams of PF-SiO2(5:4) / POA=3.5 coating and PF-SiO2(5:4) / POA=5.0 coating are shown, among which 4(ae) are SEM images of PF-SiO2(5:4) / POA=3.5 coating at different magnifications, and 4(f) is a cross-sectional view of PF-SiO2(5:4) / POA=3.5 coating on the magnesium alloy surface. Figure 3 (gi) is the SEM image of the PF-SiO2 / POA=5.0 coating at different magnifications. As can be seen from the figure, during the coating formation process, due to the lower boiling point of ethanol than butyl acetate, the coating will form micron-sized irregular aggregates during the stirring and drying process. The surface of the aggregates is PF-SiO2 ( Figure 3 (d, e)), connected by POA glue. In addition, the side of the PF-SiO2 (5:4) / POA = 3.5 coating was observed by scanning electron microscopy, and the coating thickness was measured to be about 40-45μm.

[0081] 3. Coating performance test

[0082] 1. Adhesion test

[0083] PF-SiO2 (5:4) / POA = 3.5 coatings were prepared on ABS plates and magnesium alloys, respectively. Orthogonal grid cutting tests were performed on the coating specimens using a grid cutter: first, a set of parallel cuts were made with a 1mm spacing, followed by an equal number of cuts made perpendicularly with the same spacing. The coating adhesion grade was quantitatively evaluated by calculating the ratio of the coating peeling area to the total test area. This method complies with the requirements of the GB / T9286-2021 standard.

[0084] Use 3M tape to remove the loose coating film on the cut surface. To ensure that the 3M tape is in full contact with the coating surface, roll a 100g weight over the tape surface. After applying the tape, hold the dangling end of the tape and peel it off steadily.

[0085] like Figure 4 As shown, the PPF-SiO2 (5:4) / POA = 3.5 coating has good adhesion on both glass and magnesium alloy substrates. Comparison with the test results shows that the coating's adhesion grade is 1. Furthermore, even after the adhesion evaluation, water droplets still do not penetrate the surface, indicating that the coating still has good hydrophobicity.

[0086] 2. Coating stability and universality test

[0087] 2.1 Chemical stability of superhydrophobic coatings

[0088] Depend on Figure 5 It can be seen that the PF-SiO2 (5:4) / POA = 3.5 superhydrophobic coating has strong chemical stability. The contact angles after being placed in 1MHCl and 3.5wt% NaCl solutions for 24 hours are 158.6±0.7° and 161.3±0.4°, respectively. The coating still exhibits good superhydrophobic properties.

[0089] 2.2 High temperature stability of coating

[0090] A PF-SiO2 (5:4) / POA = 3.5 coating was prepared on the surface of a magnesium alloy substrate, and its water contact angle was measured before and after being placed at 120°C, 140°C, 160°C, and 180°C for 4 hours.

[0091] Depend on Figure 6The contact angle of the PF-SiO2(5:4) / POA=3.5 coating remained essentially unchanged after exposure to temperatures of 120°C and 140°C for 4 h, indicating that the surface structure and hydrophobicity of the coating remained unchanged at 120°C and 140°C, resulting in a substantially unchanged contact angle. After exposure to temperatures of 160°C for 4 h, the contact angle of the PF-SiO2(5:4) / POA=3.5 coating decreased from 161.1±0.6° to 155.8±0.9°. After exposure to temperatures of 180°C for 4 h, the contact angle of the PF-SiO2(5:4) / POA=3.5 coating decreased from 160.5±0.9° to 148.0±0.9°. In summary, the PF-SiO2 (5:4) / POA = 3.5 superhydrophobic coating has high temperature stability and still has superhydrophobicity after being placed at a high temperature of 120-140 ° C for 4 hours, and has strong potential application value.

[0092] 3. Universality of coating

[0093] Figure 7 PF-SiO2(5:4) / POA=3.5 coatings were prepared on glass (a), magnesium alloy (b), ABS board (d), and paper (e) substrates. The PF-SiO2(5:4) / POA=3.5 coatings showed super-hydrophobic properties on these substrates, and the coatings showed good hydrophobicity to water, cola, juice, and yogurt ( Figure 7 (c, f)).

[0094] 4. Self-cleaning and anti-fouling properties of the coating

[0095] Methylene blue ( Figure 8 (a1-a4))、Grit( Figure 8 (b1-b4)), tilt the surface at a certain angle, and drip water from above the coating. It can be seen that methylene blue and gravel are left along with the water drops, and the coating surface is restored to cleanliness ( Figure 8 (a1-b4)), proving that the coating surface has a self-cleaning property similar to the "lotus effect". In addition, when the coating was immersed in a deionized methylene blue solution and taken out, the super-hydrophobic surface remained clean, while the back of the ABS board was contaminated by the methylene blue solution, proving that the super-hydrophobic surface has certain anti-fouling properties ( Figure 8 (c1-c4)).

[0096] The above is only an embodiment of the present invention, and the common knowledge such as the specific technical solutions and / or characteristics in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. A dual-size wear-resistant super-hydrophobic material based on a phase separation method, characterized by: The invention comprises double-sized ethanol-containing semi-solid PF-SiO2 nanoparticles, polyolefin glue and butyl acetate. The double-sized ethanol-containing semi-solid PF-SiO2 nanoparticles comprise large-sized semi-solid PF-SiO2 nanoparticles and small-sized semi-solid PF-SiO2 nanoparticles.

2. The dual-size wear-resistant super-hydrophobic material based on the phase separation method according to claim 1, characterized in that: The addition ratio of the double-sized ethanol-containing semi-solid PF-SiO2 nanoparticles to the polyolefin glue is 2.4-5.

0.

3. The dual-size wear-resistant super-hydrophobic material based on the phase separation method according to claim 2, characterized in that: The ratio of large-sized semi-solid PF-SiO2 nanoparticles to small-sized semi-solid PF-SiO2 nanoparticles is 5:(2-5).

4. The dual-size wear-resistant super-hydrophobic material based on the phase separation method according to claim 3, characterized in that: The particle size of the large-sized semi-solid PF-SiO2 nanoparticles is 100-200 nm.

5. The dual-size wear-resistant super-hydrophobic material based on the phase separation method according to claim 4, characterized in that: The particle size of the small-sized semi-solid PF-SiO2 nanoparticles is 10 to 20 nm.

6. A method for preparing a dual-size wear-resistant super-hydrophobic material based on a phase separation method according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Synthesis of dual-sized ethanol-containing semi-solid PF-SiO2 nanoparticles. Two SiO2 nanoparticles of different particle sizes are synthesized separately. The synthesis steps are as follows: after uniformly mixing the SiO2 nanoparticles with an ethanol solution, sodium methyl silicate is added and stirred evenly, 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (PFDTES) and tetraethyl orthosilicate are added and mechanically stirred to react to form a suspension, and the suspension is centrifuged to obtain semi-solid PF-SiO2 nanoparticles containing ethanol; S2. Dissolve polyolefin glue (POA) in butyl acetate, stir for 20-25 minutes, add large-sized semi-solid PF-SiO2 nanoparticles and small-sized semi-solid PF-SiO2 nanoparticles under stirring, and stir for 3-3.5 hours to obtain a POA / modified SiO2 suspension.

7. The method for preparing a dual-size wear-resistant super-hydrophobic material based on a phase separation method according to claim 6, characterized in that: In step S1, the addition ratio of SiO2 nanoparticles to ethanol solution is 1g: (65-75)ml; the ethanol solution includes 23 parts of ethanol and 2 parts of water.

8. The method for preparing a dual-size wear-resistant super-hydrophobic material based on a phase separation method according to claim 7, characterized in that: In step S1, the mass ratio of SiO2 nanoparticles: sodium methyl silicate: PFDTES: tetraethyl orthosilicate is 1:0.3:(1.63-1.67):0.

28.

9. The method for preparing a dual-size wear-resistant super-hydrophobic material based on a phase separation method according to claim 8, characterized in that: In step S1, the SiO2 nanoparticles are mixed with the ethanol solution by mechanical stirring for 15 min and ultrasonic treatment for 15 min.

10. a kind of double-size wear-resistant super-hydrophobic material based on phase separation method as described in claim 1-5 is applied to coating field, during use, double-size wear-resistant super-hydrophobic material is sprayed on substrate with spray gun, room temperature cures 24h, obtains phase separation super-hydrophobic coating.

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