A green and environmentally friendly super-slip coating applicable to multiple substrates and its preparation method

Abstract

The present invention discloses a green and environmentally friendly super-slip coating applicable to multiple substrates and a preparation method thereof, comprising the following steps: step 1, mixing water, a coupling agent and an organic solvent A in proportion to obtain a polymer system, sealing and heating the polymer system to make it evenly dispersed to obtain component 1; step 2, mixing polydimethylsiloxane and an organic solvent B in proportion to obtain a polymer system, and making it evenly dispersed to obtain component 2; step 3, placing a substrate into component 1 to first graft the silane coupling agent, and then placing the substrate into component 2 to covalently graft the polydimethylsiloxane, and finally thermally curing to obtain a super-slip coating; the green and environmentally friendly super-slip coating applicable to multiple substrates prepared by the present invention exhibits excellent self-cleaning performance, and has good physical and chemical stability and corrosion resistance. The preparation method is green and environmentally friendly and has great application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional materials, relates to a super-slip coating, and specifically relates to a green and environmentally friendly super-slip coating applicable to multiple substrates and a preparation method thereof. Background Art

[0002] Super-slip surfaces are smooth coatings with roughness ranging from a few nanometers to tens of nanometers, where the sliding angle of liquid is less than 10°. Due to their excellent liquid-repellent properties, these surfaces have demonstrated outstanding performance in a variety of fields, including anti-fouling, anti-corrosion, self-cleaning, pipeline transportation, medical treatment, and military applications.

[0003] The earliest super-slip coating surfaces were generally obtained by constructing micro-nano rough structures and combining them with low surface energy materials. However, the fine micro-nanostructures are easily damaged by external forces and destroyed. In addition, the solid-liquid-gas three-phase interface on its surface will also be contracted by the steam carried by the high-temperature liquid or the high pressure, resulting in a transition from the Cassie-Baxter state to the Wenzel state, and the loss of super-slip properties. In order to reduce the impact of structural defects on the liquid-repellent properties of the coating, researchers were inspired by pitcher plants and prepared perfluorinated super-slip coatings by injecting perfluorinated lubricants into micro-nanostructured substrates. Although the perfusion-type super-slip coating can repair the damage caused by physical damage due to the high fluidity of the lubricant, since the lubricant mostly relies on capillary action for fixation, washing, scouring or evaporation of the lubricant itself will lead to a reduction in the lubricant, making the super-slip performance of the coating unstable. The stability of the coating needs to be improved during the preparation of the super-slip coating. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an ultra-slip coating and a preparation method thereof that have good physical and chemical stability, corrosion resistance, excellent self-cleaning performance and can be applied to multiple substrates. The method is simple to operate, easy to implement, and green and environmentally friendly.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A green and environmentally friendly method for preparing a super-slip coating applicable to multiple substrates comprises the following steps:

[0007] Step 1: Add 100-150 mL of organic solvent A to 10-20 g of silane coupling agent, stir to disperse evenly, then add 10-15 mL of water, seal and stir for 30-60 min to hydrolyze, to obtain component 1;

[0008] Step 2: Add 50-100 mL of organic solvent B to 0.05-1 g of polydimethylsiloxane and stir to fully dissolve it to obtain component 2;

[0009] Step 3: After cleaning the substrate, place it in component 1 and heat it to 50-120°C. Soak it for 1-2 hours to graft the silane coupling agent. After drying, place it in component 2 and soak it for 20-30 minutes to covalently graft polydimethylsiloxane. Finally, heat cure it at 80-120°C for 20-40 minutes to form an ultra-slip coating on the surface of the substrate.

[0010] The present invention also has the following technical features:

[0011] Preferably, the silane coupling agent in step 1 includes any one of KH-540, KH-550, KH-560, KH-151, KH-171, KH-602 or SI-69.

[0012] Preferably, the organic solvent A comprises ethanol, methanol, ethyl acetate or acetone.

[0013] Preferably, the polydimethylsiloxane includes monoglycidyl ether-terminated polydimethylsiloxane, diglycidyl ether-terminated polydimethylsiloxane or trimethylsiloxane-terminated polydimethylsiloxane.

[0014] Preferably, the organic solvent B includes toluene, xylene, butane or n-hexane.

[0015] Preferably, the substrate in step 3 comprises fabric, metal, ceramic, plastic, wooden product or packaging box.

[0016] Preferably, the method for cleaning the substrate in step 3 includes first wiping it with anhydrous ethanol and then cleaning it with a plasma cleaner for 3 to 5 minutes.

[0017] Preferably, the drying in step 3 is carried out in an oven at 100-120° C. for 15-30 minutes.

[0018] The present invention also protects a green and environmentally friendly ultra-slip coating that is prepared by the method described above and can be applied to multiple substrates.

[0019] Compared with the prior art, the present invention has the following technical effects:

[0020] The present invention prepares a green and environmentally friendly super-slip coating applicable to multiple substrates by first grafting a silane coupling agent and then covalently grafting polydimethylsiloxane. Since polydimethylsiloxane has a low molecular weight, low surface energy, and high chain segment flexibility, its molecular chain segments exhibit high fluidity similar to that of a liquid through rotational or vibrational bending motion. After grafting, a "liquid-like" lubricating layer can be formed. At the same time, the presence of the silane coupling agent allows the coating to be tightly bonded to the substrate. The prepared super-slip coating has good physical and chemical stability, corrosion resistance, and excellent self-cleaning properties. It also does not involve the use of fluorinated materials and is green and environmentally friendly.

[0021] The preparation method of the present invention is simple to operate, easy to implement, has no special requirements for the substrate, can be used on a variety of substrates, has good application value and a wide market. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a physical picture of the plastic coating in Example 1;

[0023] Figure 2 This is a physical picture of the aluminum sheet coated in Example 2;

[0024] Figure 3 This is a physical picture of the ceramic sheet coated in Example 3;

[0025] Figure 4 This is a light microscopic image of the green and environmentally friendly super-slip coating that can be applied to multiple substrates prepared in Example 1;

[0026] Figure 5 The contact angle of the coating prepared in Example 1 on the plastic sheet before and after treatment;

[0027] Figure 6 The contact angle of the coating prepared in Example 1 on the plastic sheet before and after treatment is hexadecane;

[0028] Figure 7 is the contact angle of the coating in Example 1 to liquids with different surface tensions;

[0029] Figure 8 is the sliding angle of the coating in Example 1 for liquids with different surface tensions;

[0030] Figure 9 The contact angle and sliding angle of the coating prepared in Example 2 on aluminum sheet before and after treatment with water;

[0031] Figure 10 The contact angle and sliding angle of the coating prepared in Example 3 on the ceramic sheet before and after treatment with water;

[0032] Figure 11 This is a diagram of the sliding angle measurement equipment for the coating prepared in Example 1;

[0033] Figure 12 This is a self-cleaning performance test chart of the coating prepared in Example 1. DETAILED DESCRIPTION

[0034] The specific contents of the present invention are further explained in detail below with reference to the embodiments.

[0035] In the following examples, the purity of the organic solvent A (ethanol, methanol, ethyl acetate or acetone) used is 99.9%, and the purity of the organic solvent B (toluene, xylene, butane or n-hexane) used is 99.5%.

[0036] The average molecular weights of the polydimethylsiloxanes used are: 2000-3000;

[0037] Monoglycidyl ether terminated polydimethylsiloxane: 2000-3000;

[0038] Diglycidyl ether terminated polydimethylsiloxane: 2000~3000

[0039] Trimethylsiloxane-terminated polydimethylsiloxane: 2000~3000.

[0040] Example 1

[0041] Pretreatment of the substrate: The substrate used is a plastic sheet, which is first wiped with anhydrous ethanol and then cleaned with a plasma cleaner for 3 minutes;

[0042] Place 10 g of silane coupling agent KH-550, 150 mL of anhydrous ethanol, and 10 mL of water into a beaker, cover the beaker with plastic wrap, and stir and disperse on a magnetic stirrer at 2000 r / min for 30 min until the solution becomes colorless and transparent.

[0043] Then, the plastic sheet was placed in the hydrolysis solution and sealed and heated to 80°C. After 2 hours, the plastic sheet was taken out and dried in an oven at 120°C for 15 minutes.

[0044] Then weigh 0.05 g of monoglycidyl ether-terminated polydimethylsiloxane and mix it with 60 mL of n-hexane to allow the n-hexane to fully dissolve the monoglycidyl ether-terminated polydimethylsiloxane. Place the dried plastic sheet in it and soak for 30 minutes. Then take it out and dry it in an oven at 120°C for 20 minutes to form an ultra-slip coating on the surface of the plastic sheet.

[0045] Figure 1 This is a real picture of the plastic coating in Example 1 of the present invention; Figure 1 There is no obvious change in the appearance of the substrate before and after coating.

[0046] Figure 4 The light microscope image of the green and environmentally friendly super-slip coating applicable to multiple substrates prepared in Example 1; Figure 4 It can be seen that the coating liquid is evenly grafted onto the surface of the substrate.

[0047] Figure 5 The contact angle of the coating prepared in Example 1 on the plastic sheet before and after treatment; Figure 6The contact angle of the coating prepared in Example 1 on the plastic sheet before and after treatment is hexadecane; Figure 7 is the contact angle of the coating in Example 1 to liquids with different surface tensions; Figure 8 is the sliding angle of the coating in Example 1 for liquids with different surface tensions; Figure 11 The sliding angle measurement device of the coating prepared in Example 1 is shown in FIG. Figure 5 、 6 , 7, and 8, it can be seen that the plastic sheet covered with the coating has an excellent super-slip effect. Its contact angle with water is 85±0.5°, the sliding angle is 5.3±1.2°, and the contact angle with hexadecane is 73±1.1°, and the sliding angle is 8.3±0.7°.

[0048] Figure 12 The self-cleaning performance test diagram of the coating prepared in Example 1 is shown in FIG. Figure 12 The available coated plastic sheets have excellent self-cleaning properties.

[0049] Example 2

[0050] Pretreatment of the substrate: The substrate used is aluminum sheet, which is first wiped with anhydrous ethanol and then cleaned with a plasma cleaner for 5 minutes;

[0051] Place 15 g of silane coupling agent SI-69, 100 mL of anhydrous ethanol, and 10 mL of water into a beaker, cover the beaker with plastic wrap, and stir and disperse on a magnetic stirrer at 1800 rpm for 45 min until the solution becomes colorless and transparent.

[0052] Then, the aluminum sheet was placed in the hydrolysis solution, sealed and heated to 120°C. After 1 hour, the aluminum sheet was taken out and dried in an oven at 100°C for 20 minutes.

[0053] Then weigh 0.08 g of diglycidyl ether-terminated polydimethylsiloxane and mix it with 80 mL of toluene. Stir to allow the toluene to fully dissolve the diglycidyl ether-terminated polydimethylsiloxane. Place the dried aluminum sheet in it and soak for 20 minutes. Then take it out and dry it in an oven at 80°C for 30 minutes to form an ultra-slip coating on the surface of the aluminum sheet.

[0054] Figure 2 The actual picture of the aluminum sheet coated in Example 2; Figure 2 There is no obvious change in the appearance of the substrate before and after coating. Figure 9 The contact angle and sliding angle of the coating prepared in Example 2 on the aluminum sheet before and after treatment are shown in FIG. Figure 9 The grafted coated aluminum sheet has good super-slip properties, with a contact angle of 75±0.8° and a sliding angle of 6.2±0.2° for water; a contact angle of 62.1±1.4° and a sliding angle of 10.2±0.5° for hexadecane.

[0055] Example 3

[0056] Pretreatment of the substrate: The substrate used is a ceramic sheet, which is first wiped with anhydrous ethanol and then cleaned with a plasma cleaner for 4 minutes;

[0057] Place 20 g of silane coupling agent KH-171, 120 mL of methanol, and 15 mL of water into a beaker, cover the beaker with plastic wrap, and stir and disperse on a magnetic stirrer at 1600 rpm for 30 min until the solution becomes colorless and transparent.

[0058] The ceramic piece was then placed in the hydrolysis solution, sealed and heated to 100°C. After 1.5 hours, the ceramic piece was taken out and dried in an oven at 100°C for 15 minutes.

[0059] Then weigh 0.08 g of trimethylsiloxane-terminated polydimethylsiloxane and mix it with 60 mL of n-hexane to allow the n-hexane to fully dissolve the trimethylsiloxane-terminated polydimethylsiloxane. Place the dried ceramic sheet in it and soak for 20 minutes. Then take it out and dry it in an oven at 120°C for 30 minutes to form an ultra-slip coating on the surface of the ceramic sheet.

[0060] Figure 3 The actual picture of the ceramic sheet coated in Example 3; Figure 3 There is no obvious change in the appearance of the substrate before and after coating.

[0061] Figure 10 The contact angle and sliding angle of the coating prepared in Example 3 on the ceramic sheet before and after treatment are shown in FIG. Figure 10 It can be concluded that the ceramic sheet after coating has super-slip properties, with a contact angle of 80±0.8° and a sliding angle of 7.3±0.5° for water; a contact angle of 71.2±0.4° and a sliding angle of 9.8±0.5° for hexadecane.

[0062] Example 4

[0063] Pretreatment of the substrate: The substrate used is a cloth, which is first wiped with anhydrous ethanol and then cleaned with a plasma cleaner for 4 minutes;

[0064] Place 18 g of silane coupling agent KH-560, 130 mL of acetone, and 12 mL of water into a beaker, cover the beaker with plastic wrap, and stir and disperse on a magnetic stirrer at 1600 rpm for 60 min until the solution becomes colorless and transparent.

[0065] Then, the cloth piece was placed in the hydrolysis solution and sealed and heated to 50°C. After 2 hours, the ceramic piece was taken out and dried in an oven at 110°C for 18 minutes.

[0066] Then weigh 1 g of trimethylsiloxane-terminated polydimethylsiloxane and mix it with 100 mL of butane, allowing the butane to fully dissolve the trimethylsiloxane-terminated polydimethylsiloxane. Place the dried cloth in it and soak for 25 minutes, then take it out and dry it in an oven at 100°C for 40 minutes to form an ultra-slip coating on the surface of the cloth.

[0067] Example 5

[0068] Pretreatment of the substrate: The substrate used is wood chips, which are first wiped with anhydrous ethanol and then cleaned with a plasma cleaner for 4 minutes;

[0069] Place 16 g of silane coupling agent KH-602, 110 mL of ethyl acetate, and 10 mL of water into a beaker, cover the beaker with plastic wrap, and stir and disperse on a magnetic stirrer at 1600 rpm for 50 min until the solution becomes colorless and transparent.

[0070] Then, the wood chips were placed in the hydrolysis solution and sealed and heated to 100°C. After 1.2 hours, the ceramic pieces were taken out and dried in an oven at 120°C for 30 minutes.

[0071] Then weigh 0.5 g of monoglycidyl ether-terminated polydimethylsiloxane and mix it with 50 mL of xylene to allow the xylene to fully dissolve the monoglycidyl ether-terminated polydimethylsiloxane. Place the dried wood chips in the mixture and soak for 20 minutes. Then take them out and dry them in an oven at 120°C for 40 minutes to form an ultra-slip coating on the surface of the wood chips.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific implementation methods of the present invention may still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims.

Claims

1. A green and environmentally friendly method for preparing a super-slip coating applicable to multiple substrates, characterized in that: The following steps are involved: Step 1: Add 100-150 mL of organic solvent A to 10-20 g of silane coupling agent, stir to disperse evenly, then add 10-15 mL of water, seal and stir for 30-60 min to hydrolyze, to obtain component 1; Step 2: Add 50-100 mL of organic solvent B to 0.05-1 g of polydimethylsiloxane, and stir to fully dissolve it to obtain component 2; the polydimethylsiloxane includes monoglycidyl ether-terminated polydimethylsiloxane, diglycidyl ether-terminated polydimethylsiloxane, or trimethylsiloxane-terminated polydimethylsiloxane; Step 3: After cleaning the substrate, place it in component 1 and heat it to 50-120°C. Soak it for 1-2 hours to graft the silane coupling agent. After drying, place it in component 2 and soak it for 20-30 minutes to covalently graft polydimethylsiloxane. Finally, heat cure it at 80-120°C for 20-40 minutes to form an ultra-slip coating on the surface of the substrate.

2. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The silane coupling agent described in step 1 includes any one of KH-540, KH-550, KH-560, KH-151, KH-171, KH-602 or SI-69.

3. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The organic solvent A includes ethanol, methanol, ethyl acetate or acetone.

4. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The organic solvent B includes toluene, xylene, butane or n-hexane.

5. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The substrate in step 3 includes fabric, metal, ceramic, plastic, wood or packaging box.

6. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The cleaning method of the substrate in step 3 includes first wiping with anhydrous ethanol and then cleaning with a plasma cleaner for 3 to 5 minutes.

7. The method for preparing a green and environmentally friendly super-slip coating applicable to multiple substrates according to claim 1, characterized in that: The drying in step 3 is carried out in an oven at 100-120° C. for 15-30 minutes.

8. A green and environmentally friendly ultra-slip coating applicable to multiple substrates, prepared by the method according to any one of claims 1 to 7.

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