Preparation method and application of supramolecular self-assembled hydrophobic active agent

Abstract

This invention relates to a method for preparing and applying a supramolecular self-assembled hydrophobic surfactant, belonging to the fields of supramolecular coordination chemistry, surface modification engineering, and hydrophobic coating technology. In this invention, 1,8-octanediamine reacts with 4-aldehyde imidazolium to prepare a Schiff base ligand. This ligand can form supramolecular aggregates with the help of zinc ions in a solvent. The aggregates electrically attract 1H,1H,2H,2H-perfluoro-1-ols to their outer surfaces, self-assembling into a supramolecular self-assembled hydrophobic surfactant. This surfactant can be applied in the field of hydrophobic coatings, producing coatings with lotus leaf-like structures and hydrophobic wax properties, exhibiting excellent hydrophobic performance.

Description

Technical Field

[0001] This invention relates to a method for preparing and applying a supramolecular self-assembled hydrophobic surfactant, belonging to the fields of surface modification engineering and hydrophobic coatings. Background Technology

[0002] Due to the difficulty of liquid droplets adhering to hydrophobic surfaces, these surfaces possess properties such as waterproofing, anti-icing, anti-fogging, and self-cleaning. In the aerospace field, hydrophobic coatings on aircraft surfaces effectively prevent icing, ensuring flight performance and preventing air disasters. In the transportation field, hydrophobic coatings prevent glass fogging, ensuring clear visibility and driving safety. In the electronics and electrical fields, hydrophobic coatings prevent water accumulation on circuit boards, preventing short circuits or rust in electronic components. In everyday life, hydrophobic coatings can prevent food from sticking to the bottom of pots and pans. Therefore, hydrophobic surfaces have a very wide range of applications.

[0003] The study of lotus leaf-like structures has long been a focus for researchers of hydrophobic coatings. The surface of a lotus leaf has a dense structure of micro-protrusions, approximately 5 micrometers in height. Further magnification reveals a layer of nanoscale papillae, approximately 200 nanometers in height, attached to the surface of these micro-protrusions. In addition, the lotus leaf secretes a layer of bio-wax on its surface to protect against external aggressors. It is this combination of surface micro-nano composite structure and bio-wax that gives the lotus leaf its unique hydrophobic properties, making it difficult for water droplets to remain on its surface. As the droplets quickly roll off the surface, they carry away dust and debris, achieving self-cleaning. Currently, the preparation of hydrophobic surfaces largely focuses on the preparation and coating of bio-waxes, primarily using perfluorinated compounds or other low surface energy materials. However, the micro-nano structure of the lotus leaf is more challenging due to the need for precise structural design.

[0004] Early research primarily focused on chemical synthesis methods. Fluorides are poorly soluble in water and conventional organic solvents, but readily soluble in organofluorine solvents. Therefore, when performing hydrophobic surface treatments on materials, it is necessary to impregnate them with fluorinated organic solvents. This method, due to the toxicity of organic solvents, is considered unenvironmentally friendly and its applications are limited. Consequently, the preparation of green and environmentally friendly waterborne superhydrophobic coatings using aqueous solvents instead of volatile organic solvents is gaining traction. To date, several preparation methods have been explored, such as wet chemical processes for polymer-particulate dispersions, electrochemical deposition, template methods, etching methods, sol-gel methods, and hydrothermal methods. However, a major challenge remains how to coat the substrate surface with a low-surface-energy hydrophobic material while also imbuing it with a lotus-leaf-like microscopic hydrophobic structure. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of existing technologies, abandon the traditional single covalent interaction, and utilize the non-covalent interactions of supramolecular chemistry. First, Schiff base ligands are synthesized using aldehyde and amino groups. Then, the non-covalent interaction between imidazole and zinc ions is used to achieve the self-assembly of the first layer of micelles. The electron-withdrawing effect of perfluorinated compounds achieves the self-assembly of the second layer of micelles, constructing a nanoscale lotus leaf-inspired biomimetic structure. This biomimetic material itself is hydrophobic, and it also possesses a microscopic hydrophobic structure resembling a lotus leaf, exhibiting excellent hydrophobicity.

[0006] The technical solution of this invention is:

[0007] A supramolecular self-assembled hydrophobic active agent, comprising a ligand, 1H,1H,2H,2H-perfluoro-1-ol, zinc chloride crosslinking agent, and anhydrous ethanol;

[0008] The zinc chloride crosslinking agent, ligand, and 1H,1H,2H,2H-perfluoro-1-ol self-assemble into micelles and dispersed in anhydrous ethanol;

[0009] The ratio of the zinc chloride crosslinking agent, ligand, 1H,1H,2H,2H-perfluoro-1-ol and anhydrous ethanol is 1 mmol: 1-2 mmol: 1-3 mmol: 100 ml.

[0010] The method for preparing the ligand is as follows:

[0011] An anhydrous ethanol solution of 1,8-octanediamine, an anhydrous ethanol solution of 4-aldehyde imidazole, and glacial acetic acid were mixed and reacted. The product was then dried in a vacuum oven at 85-95°C for 4.5-5.5 hours after the solvent was evaporated in a fume hood for 12-15 hours to obtain the ligand.

[0012] In the anhydrous ethanol solution of 1,8-octanediamine, the ratio of 1,8-octanediamine to anhydrous ethanol is 0.05 mol: 20-30 ml.

[0013] In the anhydrous ethanol solution of 4-aldehyde imidazole, the ratio of 4-aldehyde imidazole to anhydrous ethanol is 0.1 mol: 15-25 ml.

[0014] The ratio of 1,8-octanediamine, 4-aldehyde imidazole, and glacial acetic acid is 0.05 mol: 0.1 mol: 3-5 ml.

[0015] The reaction temperature is 70-80℃, and the reaction time is 4-5 hours.

[0016] A method for preparing a supramolecular self-assembled hydrophobic active agent, comprising the following steps:

[0017] An ethanol solution of the ligand, an anhydrous ethanol solution of 1H,1H,2H,2H-perfluoro-1-ol, and an ethanol solution of zinc chloride were mixed and stirred to obtain a supramolecular self-assembled hydrophobic active agent.

[0018] The concentration of anhydrous ethanol in the ligand is 25 mmol / L;

[0019] The concentration of the anhydrous ethanol solution of zinc chloride is 25 mmol / L;

[0020] The concentration of the anhydrous ethanol solution of the 1H,1H,2H,2H-perfluoro-1-ol is 50 mmol / L.

[0021] The volume ratio of the zinc chloride ethanol solution, the ligand ethanol solution, and the anhydrous ethanol solution of 1H,1H,2H,2H-perfluoro-1-ol is 2:1-2:1-3.

[0022] The application of a supramolecular self-assembled hydrophobic surfactant in the field of hydrophobic coatings includes the following steps:

[0023] The substrate is immersed in a supramolecular self-assembled hydrophobic surfactant. After immersion, the substrate is removed and dried to obtain a hydrophobic substrate modified with a supramolecular self-assembled hydrophobic surfactant.

[0024] The soaking time is 0.5-1 hour.

[0025] Beneficial effects

[0026] In this invention, the coordination principle of zinc ions and the non-covalent interaction of low surface energy materials are utilized. First, a Schiff base ligand is synthesized by using 4-aldehyde imidazole and 1,8-octanediamine. Then, the imidazole group coordinates with zinc ions to achieve the first layer self-assembly. The electron-withdrawing effect of the perfluorinated compound achieves the second layer self-assembly, thus constructing a nanoscale lotus leaf biomimetic structure. This biomimetic material itself is hydrophobic, and at the same time, it has a micro-hydrophobic structure that mimics the lotus leaf, thus exhibiting good hydrophobicity. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of supramolecular self-assembly micelles;

[0028] Figure 2 This is a cryo-transmission electron microscope image of micelles in water.

[0029] Figure 3 This is a test diagram of the contact angle of a substrate that has not undergone hydrophobic treatment.

[0030] Figure 4 This is a SEM image of the lotus leaf-like structure on the surface of the substrate after surface modification with surfactant in Example 1.

[0031] Figure 5The contact angle test is performed on the substrate after surface modification with surfactant in Example 1.

[0032] Figure 6 This is a SEM image of the lotus leaf-like structure on the surface of the substrate after surface modification with surfactant in Example 2.

[0033] Figure 7 This is a contact angle test of the substrate after surface modification with surfactant in Example 2. Detailed Implementation

[0034] The present invention will be further illustrated by the following embodiments, but the embodiments do not limit the scope of protection of the present invention.

[0035] A supramolecular self-assembled hydrophobic surfactant comprising a ligand, 1H,1H,2H,2H-perfluoro-1-ol, zinc chloride crosslinking agent, and anhydrous ethanol; such as Figure 1 and Figure 2 As shown;

[0036] The zinc chloride crosslinking agent, ligand, and 1H,1H,2H,2H-perfluoro-1-ol self-assemble into micelles and dispersed in anhydrous ethanol;

[0037] The ratio of the zinc chloride crosslinking agent, ligand, 1H,1H,2H,2H-perfluoro-1-ol and anhydrous ethanol is 1 mmol: 1-2 mmol: 1-3 mmol: 100 ml.

[0038] A supramolecular self-assembled hydrophobic surfactant is prepared by means of main raw materials and auxiliary raw materials. The main raw materials include 1H,1H,2H,2H-perfluoro-1-ol, zinc chloride, 1,8-octanediamine, and 4-aldehyde imidazole. The auxiliary raw materials are catalyst and solvent.

[0039] The catalyst is glacial acetic acid, and the solvent is anhydrous ethanol.

[0040] A method for preparing a ligand, comprising the following steps:

[0041] First, add 0.05 mol of 1,8-octanediamine to a beaker, and dissolve it in 25 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 1,8-octanediamine. Then, transfer the anhydrous ethanol solution of 1,8-octanediamine to a 250 ml three-necked flask.

[0042] The second step involves adding 0.1 mol of 4-aldehyde imidazole to a beaker and dissolving it in 20 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 4-aldehyde imidazole. The anhydrous ethanol solution of 4-aldehyde imidazole is then transferred into a 25 ml constant-pressure separatory funnel, which is then assembled into the three-necked flask described in the first step.

[0043] The third step is to heat and stir the three-necked flask until it reaches 70°C, then add 3-5 ml of glacial acetic acid, open the constant pressure separatory funnel, and let the anhydrous ethanol solution of 4-aldehyde imidazole be added dropwise to the three-necked flask continuously.

[0044] Fourth step: After reacting for 5 hours, pour the product solution into a beaker, cover it with plastic wrap and poke some holes in it, and place it in a fume hood to evaporate the solvent for 12-15 hours to obtain a viscous mixture of ligand and glacial acetic acid.

[0045] Fifth step: Place the viscous mixture obtained in the fourth step into a vacuum oven and dry it at 90°C for 5 hours to remove glacial acetic acid and obtain the ligand.

[0046] A method for preparing a supramolecular self-assembled hydrophobic active agent, comprising the following steps:

[0047] First, add 10 ml of a 25 mmol / L anhydrous ethanol solution of zinc chloride to a beaker, followed by a 25 mmol / L anhydrous ethanol solution of the ligand (the volume ratio of the ligand solution to the zinc chloride solution is 1:1-2). Then stir for 30 minutes and let stand for 1 hour to obtain the preliminary complexation solution.

[0048] In the second step, a 50 mmol / L anhydrous ethanol solution of 1H,1H,2H,2H-perfluoro-1-ol (volume ratio of 1H,1H,2H,2H-perfluoro-1-ol to zinc chloride solution is 1:1-3) is added to the preliminary coordination solution obtained in the first step. Any remaining solution less than 60 ml is made up with anhydrous ethanol. The mixture is stirred for 10 minutes to obtain a supramolecular self-assembled hydrophobic active agent.

[0049] The application of a supramolecular self-assembled hydrophobic surfactant in the field of hydrophobic coatings includes the following steps:

[0050] The first step is to immerse the substrate in a supramolecular self-assembled hydrophobic surfactant and stir continuously for 2 hours.

[0051] The second step is to remove the substrate and place it in a forced-air drying oven for 2 hours to dry the anhydrous ethanol on the surface of the substrate, thereby obtaining a substrate modified with supramolecular self-assembled hydrophobic surfactant.

[0052] Example 1

[0053] A method for preparing a ligand, comprising the following steps:

[0054] First, add 0.05 mol of 1,8-octanediamine to a beaker, and dissolve it in 25 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 1,8-octanediamine. Then, transfer the anhydrous ethanol solution of 1,8-octanediamine to a 250 ml three-necked flask.

[0055] The second step involves adding 0.1 mol of 4-aldehyde imidazole to a beaker and dissolving it in 20 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 4-aldehyde imidazole. The anhydrous ethanol solution of 4-aldehyde imidazole is then transferred into a 25 ml constant-pressure separatory funnel, which is then assembled into the three-necked flask described in the first step.

[0056] The third step is to heat and stir the three-necked flask until it reaches 70°C, then add 5 ml of glacial acetic acid, open the constant pressure separatory funnel, and let the anhydrous ethanol solution of 4-aldehyde imidazole be added dropwise to the three-necked flask.

[0057] Fourth step: After reacting for 5 hours, pour the product solution into a beaker, cover it with plastic wrap and poke some holes in it, and place it in a fume hood to evaporate the solvent for 15 hours to obtain a viscous mixture of ligand and glacial acetic acid.

[0058] Fifth step: Place the viscous mixture obtained in the fourth step into a vacuum oven and dry it at 90°C for 5 hours to remove glacial acetic acid and obtain the ligand.

[0059] A method for preparing a supramolecular self-assembled hydrophobic active agent, comprising the following steps:

[0060] First, add 10 ml of a 25 mmol / L anhydrous ethanol solution of zinc chloride to a beaker, followed by 20 ml of a 25 mmol / L anhydrous ethanol solution of the ligand. Stir for 30 minutes and let stand for 1 hour to obtain the preliminary complexation solution.

[0061] In the second step, 30 ml of anhydrous ethanol solution of 50 mmol / L 1H,1H,2H,2H-perfluoro-1-ol was added to the preliminary coordination solution obtained in the first step. The mixture was stirred for 10 minutes to obtain a supramolecular self-assembled hydrophobic active agent.

[0062] The application of a supramolecular self-assembled hydrophobic surfactant in the field of hydrophobic coatings includes the following steps:

[0063] The first step is to immerse the substrate in a supramolecular self-assembled hydrophobic surfactant and stir continuously for 2 hours.

[0064] The second step is to remove the substrate and place it in a forced-air drying oven for 2 hours to dry the anhydrous ethanol on the surface of the substrate, thereby obtaining a substrate modified with supramolecular self-assembled hydrophobic surfactant.

[0065] Contact angle test diagram of untreated hydrophobic substrate as shown in the figure Figure 3 As shown, the contact angle is 73.3°; Figure 4 This is a SEM image of the lotus leaf-like structure on the surface of the substrate after surface modification with surfactants in Example 1. Figure 5 The contact angle of the substrate after surface modification with the surfactant in Example 1 was 158.8°. Figure 4It can be seen that the substrate surface after surface modification with surfactant in Example 1 has a lotus leaf-like structure. Figure 5 It can be seen that the substrate modified with surfactant in Example 1 has good hydrophobicity.

[0066] Example 2

[0067] A method for preparing a ligand, comprising the following steps:

[0068] First, add 0.05 mol of 1,8-octanediamine to a beaker, and dissolve it in 25 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 1,8-octanediamine. Then, transfer the anhydrous ethanol solution of 1,8-octanediamine to a 250 ml three-necked flask.

[0069] The second step involves adding 0.1 mol of 4-aldehyde imidazole to a beaker and dissolving it in 20 ml of anhydrous ethanol to prepare an anhydrous ethanol solution of 4-aldehyde imidazole. The anhydrous ethanol solution of 4-aldehyde imidazole is then transferred into a 25 ml constant-pressure separatory funnel, which is then assembled into the three-necked flask described in the first step.

[0070] The third step is to heat and stir the three-necked flask until it reaches 70°C, then add 5 ml of glacial acetic acid, open the constant pressure separatory funnel, and let the anhydrous ethanol solution of 4-aldehyde imidazole be added dropwise to the three-necked flask.

[0071] Fourth step: After reacting for 5 hours, pour the product solution into a beaker, cover it with plastic wrap and poke some holes in it, and place it in a fume hood to evaporate the solvent for 15 hours to obtain a viscous mixture of ligand and glacial acetic acid.

[0072] Fifth step: Place the viscous mixture obtained in the fourth step into a vacuum oven and dry it at 90°C for 5 hours to remove glacial acetic acid and obtain the ligand.

[0073] A method for preparing a supramolecular self-assembled hydrophobic active agent, comprising the following steps:

[0074] First, add 10 ml of a 25 mmol / L anhydrous ethanol solution of zinc chloride to a beaker, followed by 10 ml of a 25 mmol / L anhydrous ethanol solution of the ligand. Stir for 30 minutes and let stand for 1 hour to obtain the preliminary complexation solution.

[0075] In the second step, 20 ml of anhydrous ethanol solution of 50 mmol / L 1H,1H,2H,2H-perfluoro-1-ol was added to the preliminary coordination solution obtained in the first step. An additional 20 ml of anhydrous ethanol was then added, and the mixture was stirred for 10 minutes to obtain a supramolecular self-assembled hydrophobic active agent.

[0076] The application of a supramolecular self-assembled hydrophobic surfactant in the field of hydrophobic coatings includes the following steps:

[0077] The first step is to immerse the substrate in a supramolecular self-assembled hydrophobic surfactant and stir continuously for 2 hours.

[0078] The second step is to remove the substrate and place it in a forced-air drying oven for 2 hours to dry the anhydrous ethanol on the surface of the substrate, thereby obtaining a substrate modified with supramolecular self-assembled hydrophobic surfactant.

[0079] Figure 6 This is a SEM image of the lotus leaf-like structure on the surface of the substrate after surface modification with surfactants, as shown in Example 2. Figure 7 The contact angle of the substrate after surfactant surface modification in Example 2 was 146.5°. Figure 6 It can be seen that the substrate surface after surface modification with surfactant in Example 2 has a lotus leaf-like structure. Figure 7 It can be seen that the substrate modified with surfactant in Example 2 has good hydrophobicity.

[0080] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a supramolecular self-assembled hydrophobic surfactant, characterized in that... The steps are as follows: An ethanol solution of the ligand, an anhydrous ethanol solution of 1H,1H,2H,2H-perfluoro-1-ol, and an ethanol solution of zinc chloride were mixed and stirred to obtain a supramolecular self-assembled hydrophobic active agent. The method for preparing the ligand is as follows: An anhydrous ethanol solution of 1,8-octanediamine, an anhydrous ethanol solution of 4-aldehyde imidazole, and glacial acetic acid were mixed and reacted. The product was then dried in a vacuum oven at 85-95°C for 4.5-5.5 hours after the solvent was evaporated in a fume hood for 12-15 hours to obtain the ligand. In the anhydrous ethanol solution of 1,8-octanediamine, the ratio of 1,8-octanediamine to anhydrous ethanol is 0.05 mol: 20-30 ml. In the anhydrous ethanol solution of 4-aldehyde imidazole, the ratio of 4-aldehyde imidazole to anhydrous ethanol is 0.1 mol: 15-25 ml. The ratio of 1,8-octanediamine, 4-aldehyde imidazole, and glacial acetic acid is 0.05 mol: 0.1 mol: 3-5 ml.

2. The method for preparing a supramolecular self-assembled hydrophobic surfactant according to claim 1, characterized in that: The reaction temperature is 70-80℃, and the reaction time is 4-5 hours.

3. The method for preparing a supramolecular self-assembled hydrophobic surfactant according to claim 1, characterized in that: The concentration of anhydrous ethanol in the ligand is 25 mmol / L; The concentration of the anhydrous ethanol solution of zinc chloride is 25 mmol / L; The concentration of the anhydrous ethanol solution of the 1H,1H,2H,2H-perfluoro-1-ol is 50 mmol / L. The volume ratio of the zinc chloride ethanol solution, the ligand ethanol solution, and the anhydrous ethanol solution of 1H,1H,2H,2H-perfluoro-1-ol is 2:1-2:1-3.

4. The application of a supramolecular self-assembled hydrophobic surfactant in the field of hydrophobic coatings, characterized in that... The steps are as follows: The substrate is immersed in the supramolecular self-assembled hydrophobic surfactant prepared by any of the methods in claims 1-3. After immersion, the substrate is removed and dried to obtain a hydrophobic substrate modified with supramolecular self-assembled hydrophobic surfactant.

5. The application of the supramolecular self-assembled hydrophobic surfactant according to claim 4 in the field of hydrophobic coatings, characterized in that: The soaking time is 0.5-1 hour.

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