A supramolecular aggregate surfactant

Abstract

The present invention relates to a supramolecular aggregate surfactant, and belongs to the fields of supramolecular coordination chemistry, surface modification engineering and hydrophobic coating technology. In the present invention, 4-hydroxypyridine-2,6-dicarboxylic acid and malonic acid prepare an adhesive ligand, and with the help of the coordination of the carboxyl structure and lanthanum ions on 4-hydroxypyridine-2,6-dicarboxylic acid and perfluorooctanoic acid, a supramolecular aggregate in a nano-aggregated state is obtained, which is self-assembled into a supramolecular aggregate surfactant. The active agent can solubilize fluoride and can also be applied in the field of hydrophobic coatings. The coating has the characteristics of imitating lotus leaf structure and hydrophobic wax, and has good hydrophobic properties.

Description

Technical Field

[0001] The invention relates to a supramolecular aggregate surfactant, and belongs to the fields of supramolecular coordination chemistry, surface modification engineering and hydrophobic coating. Background Art

[0002] Because droplets are difficult to settle on hydrophobic surfaces, these surfaces possess properties such as water repellency, anti-icing, anti-fogging, and self-cleaning. In the aerospace field, hydrophobic coatings on aircraft surfaces effectively prevent icing on the fuselage, ensuring flight performance and preventing air crashes. In transportation, hydrophobic coatings prevent glass fogging, ensuring clear vision and driving safety. In the electrical and electronics field, hydrophobic coatings prevent water accumulation on circuit boards, preventing short circuits and rusting of electronic components. In everyday life, hydrophobic coatings can prevent the bottoms of pots from sticking. Therefore, hydrophobic surfaces have a wide range of applications.

[0003] Imitation of lotus leaf structure has always been the research direction of researchers of hydrophobic coatings. The surface of lotus leaves has a dense micro-protrusion structure with a height of about 5 microns. Further magnification and observation can reveal that a layer of nano-scale papillae is attached to the surface of the micro-protrusions, with a height of about 200 nanometers. In addition, lotus leaves secrete a layer of biological wax on their surface to resist external invasion. It is precisely this characteristic of the combination of surface micro-nano composite structure and biological wax that gives lotus leaves unique hydrophobic properties, making it difficult for water droplets to stay on the surface of lotus leaves. In the process of rapid rolling down the surface, the droplets will carry away dust and debris on the surface, achieving self-cleaning. At present, the ideas for preparing hydrophobic surfaces are mostly focused on the preparation and coating of biological wax, mainly through perfluorinated compounds or other low surface energy materials. From the perspective of imitating the micro-nano structure of lotus leaves, it is more difficult because the structural construction requires fine design.

[0004] Early research mainly focuses on chemical synthesis methods, and fluoride is soluble in organic fluoride solvents because it is insoluble in water and conventional organic solvents. Therefore, when the material is subjected to hydrophobic surface treatment, it is necessary to infiltrate fluorinated organic solvents. This treatment method is considered to be not green enough because of the toxicity of the organic solvent and is restricted in application. Therefore, the preparation of green and environment-friendly water-based super-hydrophobic coatings using aqueous solvents as substitutes for volatile organic solvents is increasingly emerging. So far, some preparation methods have been explored, such as the wet chemical process of polymer-particle dispersions, electrochemical deposition, template method, etching method, sol-gel method and hydrothermal method. However, how to coat the substrate surface with a hydrophobic material having low surface energy and to make this material have the microscopic hydrophobic structure of imitating lotus leaves is a major problem at present. Summary of the Invention

[0005] The present invention overcomes the shortcomings of existing technologies by utilizing non-covalent interactions in supramolecular chemistry to prepare supramolecular nanoaggregates of surfactants. First, a binding ligand is prepared using 4-hydroxypyridine-2,6-dicarboxylic acid and malonic acid. The carboxyl groups on 4-hydroxypyridine-2,6-dicarboxylic acid and perfluorooctanoic acid coordinate with metal ions to form nanoaggregates of supramolecular aggregates. Because the perfluoro chain segments of perfluorooctanoic acid are located outside the aggregates, the surfactant solubilizes fluoride. When coordinated with rare earth metals, it exhibits a fluorescent effect, making it suitable for use as a fluorescent surfactant. Furthermore, due to its nanoscale size, the surfactant can form a lotus leaf-like structure when applied to a substrate surface, rendering the surface hydrophobic.

[0006] The technical solution of the present invention is:

[0007] A supramolecular aggregate surfactant comprising an adhesive ligand, perfluorooctanoic acid, a lanthanum chloride crosslinker, and anhydrous ethanol;

[0008] The adhesive ligand, perfluorooctanoic acid and lanthanum chloride crosslinker self-assemble into micelles and are dispersed in anhydrous ethanol;

[0009] The ratio of the lanthanum chloride crosslinking agent, the adhesive ligand, perfluorooctanoic acid and anhydrous ethanol is 1mmol:3-5mmol:4-5mmol:100ml.

[0010] The preparation method of the adhesive ligand is as follows:

[0011] A toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid and a toluene solution of malonic acid are mixed and reacted in cyclohexane as a water agent. After the reaction, the filtrate is dried in a vacuum oven at 85-95° C. for 4.5-5.5 hours to obtain a sticky ligand.

[0012] In the toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid, the ratio of 4-hydroxypyridine-2,6-dicarboxylic acid to toluene is 0.1 mol:20-30 ml;

[0013] In the toluene solution of malonic acid, the ratio of malonic acid to toluene is 0.05 mol:20-30 ml;

[0014] The volume ratio of the cyclohexane water-carrying agent to the total amount of toluene is 4:5, and the total amount of toluene refers to the volume sum of the toluene in the toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid and the toluene in the toluene solution of malonic acid;

[0015] The molar ratio of the 4-hydroxypyridine-2,6-dicarboxylic acid to malonic acid is 2:1.

[0016] The reaction temperature is 100-120°C and the reaction time is 4-5h.

[0017] A method for preparing a supramolecular aggregate surfactant comprises the following steps:

[0018] The ethanol solution of the binding ligand, the ethanol solution of perfluorooctanoic acid and the ethanol solution of lanthanum chloride are mixed and stirred to obtain a supramolecular aggregate surfactant.

[0019] The concentration of the ethanol solution of the binding ligand is 25 mmol / L;

[0020] The concentration of the lanthanum chloride ethanol solution is 25mmol / L;

[0021] The concentration of the perfluorooctanoic acid ethanol solution is 25 mmol / L;

[0022] The volume ratio of the lanthanum chloride ethanol solution, the binding ligand ethanol solution and the perfluorooctanoic acid ethanol solution is 1:3-5:4-5.

[0023] A supramolecular aggregate surfactant is used in the field of hydrophobic coatings, comprising the steps of: immersing a substrate in the supramolecular aggregate surfactant, removing the substrate after immersion, and drying the substrate to obtain a hydrophobic substrate modified with the supramolecular aggregate surfactant. The immersion time is 0.5-1 hour.

[0024] The supramolecular surfactant is added into the insoluble fluoride perfluorodecanol and stirred, so that the insoluble perfluorodecanol can be dissolved.

[0025] The ratio of the mass of the insoluble fluoride to the added supramolecular aggregate surfactant is 0.1 g: 5-10 ml.

[0026] Beneficial effects

[0027] The present invention utilizes 4-hydroxypyridine-2,6-dicarboxylic acid and malonic acid esterification to prepare a clamp-type adhesive ligand. This adhesive ligand can bind lanthanum ions to form supramolecular aggregates. The lanthanum ions in the supramolecular aggregates attract the carboxyl groups of perfluorooctanoic acid, leaving perfluoro chain segments in the outer shell of the aggregates, and self-assemble into a supramolecular aggregate surfactant. The coordination of the carboxyl groups and the rare earth metals can make the supramolecular aggregate surfactant fluorescent. The perfluoro chains in the outer shell of the aggregates can cause the active agent to solubilize the perfluoro compound. At the same time, due to its nanoscale, the active agent can form a lotus leaf-like structure when used on the surface of a substrate, making the substrate surface hydrophobic. Therefore, this surfactant can be used in the field of hydrophobic coatings to increase the hydrophobicity of the material. According to the fluorescence attenuation of the coating, the degree of wear of the coating can be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of self-assembly of supramolecular aggregates in nano-aggregate state;

[0029] Figure 2 This is a cryo-transmission electron microscopy image of nano-aggregated supramolecular aggregates in water.

[0030] Figure 3 This is the contact angle test diagram of the substrate without hydrophobic treatment. (73.3°)

[0031] Figure 4 This is an SEM image of the lotus leaf structure on the substrate surface after surface modification with the active agent in Example 1.

[0032] Figure 5 This is the contact angle test of the substrate after surface modification with the active agent in Example 1. (147.6°)

[0033] Figure 6 This is an SEM image of the lotus leaf structure on the substrate surface after surface modification with the active agent in Example 2.

[0034] Figure 7 This is the contact angle test of the substrate after surface modification with the active agent in Example 2 (145.1°). DETAILED DESCRIPTION

[0035] The present invention will be further described below by way of examples, but the examples do not limit the scope of protection of the present invention.

[0036] A supramolecular aggregate surfactant comprising an adhesive ligand, perfluorooctanoic acid, a lanthanum chloride crosslinker, and anhydrous ethanol;

[0037] The adhesive ligand, perfluorooctanoic acid and lanthanum chloride crosslinker self-assemble into micelles and disperse in anhydrous ethanol, such as Figure 1 and Figure 2 As shown;

[0038] The ratio of the lanthanum chloride crosslinking agent, the adhesive ligand, perfluorooctanoic acid and anhydrous ethanol is 1mmol:3-5mmol:4-5mmol:100ml.

[0039] A supramolecular aggregate surfactant, the preparation raw materials include main raw materials and auxiliary raw materials, the main raw materials include 4-hydroxypyridine-2,6-dicarboxylic acid, malonic acid, anhydrous lanthanum chloride, perfluorooctanoic acid, and the auxiliary raw materials are water-carrying agent and solvent.

[0040] The water-carrying agent is cyclohexane, and the solvent is toluene and anhydrous ethanol.

[0041] A method for preparing an adhesive ligand, comprising the following steps:

[0042] The first step is to add 0.05 mol of malonic acid into a beaker, dissolve it in 20 ml of toluene, and stir evenly to prepare a toluene solution of malonic acid.

[0043] In the second step, 0.1 mol of 4-hydroxypyridine-2,6-dicarboxylic acid was added to a beaker, dissolved in 20 ml of toluene, and stirred evenly to obtain a toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid. The toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid was then transferred to a three-necked flask.

[0044] In the third step, the malonic acid toluene solution obtained in the first step is transferred into a constant pressure separatory funnel and assembled with the three-necked flask in the second step.

[0045] Step 4: Add 10 ml of cyclohexane to the three-necked flask and heat to 110°C for 4 hours. During the reaction, keep one port open to facilitate the discharge of the mixed vapor of cyclohexane and water, and add 7 ml of cyclohexane every hour.

[0046] Step 5: Observe the flask for bubbling. If so, continue heating at 110°C until no more bubbles are produced.

[0047] In the sixth step, the solution obtained in the fifth step is transferred out and placed in a vacuum oven, and dried at 95° C. for 5 hours to obtain a bonding ligand.

[0048] A method for preparing a supramolecular aggregate surfactant comprises the following steps:

[0049] In the first step, the adhesive ligand is configured into a 25 mmol / L anhydrous ethanol solution, lanthanum chloride is configured into a 25 mmol / L anhydrous ethanol solution, and perfluorooctanoic acid is configured into a 25 mmol / L anhydrous ethanol solution as the coordination raw materials of the supramolecular aggregate surfactant.

[0050] In the second step, 10 ml of lanthanum chloride solution, a binding ligand solution (volume ratio of lanthanum chloride solution to binding ligand solution 1:3-5), and a perfluorooctanoic acid solution (volume ratio of lanthanum chloride solution to perfluorooctanoic acid solution 1:4-5) were added to a beaker. The mixture was stirred for 20 minutes and allowed to stand for 10 minutes to obtain a supramolecular aggregate surfactant.

[0051] An application of a supramolecular aggregate surfactant in the field of hydrophobic coatings comprises the following steps:

[0052] In the first step, the substrate was immersed in the supramolecular aggregate surfactant and stirred continuously for 2 hours. The contact angle test of the substrate without hydrophobic treatment is shown in the figure below. Figure 3 As shown, the contact angle is 73.3°;

[0053] In the second step, the substrate is taken out and placed in a forced air oven for 2 hours to dry the substrate to obtain a supramolecular aggregate surfactant-modified material.

[0054] Example 1

[0055] A method for preparing an adhesive ligand, comprising the following steps:

[0056] The first step is to add 0.05 mol of malonic acid into a beaker, dissolve it in 20 ml of toluene, and stir evenly to prepare a toluene solution of malonic acid.

[0057] In the second step, 0.1 mol of 4-hydroxypyridine-2,6-dicarboxylic acid was added to a beaker, dissolved in 20 ml of toluene, and stirred evenly to obtain a toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid. The toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid was then transferred to a three-necked flask.

[0058] In the third step, the malonic acid toluene solution obtained in the first step is transferred into a constant pressure separatory funnel and assembled with the three-necked flask in the second step.

[0059] Step 4: Add 10 ml of cyclohexane to the three-necked flask and heat to 110°C for 4 hours. During the reaction, keep one port open to facilitate the discharge of the mixed vapor of cyclohexane and water, and add 7 ml of cyclohexane every hour.

[0060] Step 5: Observe the flask for bubbling. If so, continue heating at 110°C until no more bubbles are produced.

[0061] In the sixth step, the solution obtained in the fifth step is transferred out and placed in a vacuum oven, and dried at 95° C. for 5 hours to obtain a bonding ligand.

[0062] A method for preparing a supramolecular aggregate surfactant comprises the following steps:

[0063] In the first step, the adhesive ligand is configured into a 25 mmol / L anhydrous ethanol solution, lanthanum chloride is configured into a 25 mmol / L anhydrous ethanol solution, and perfluorooctanoic acid is configured into a 25 mmol / L anhydrous ethanol solution as the coordination raw materials of the supramolecular aggregate surfactant.

[0064] In the second step, 10 ml of lanthanum chloride solution, 40 ml of binding ligand solution, and 40 ml of perfluorooctanoic acid solution were added to a beaker. Then, 10 ml of anhydrous ethanol was added, stirred for 20 minutes, and allowed to stand for 10 minutes to obtain a supramolecular aggregate surfactant.

[0065] An application of a supramolecular aggregate surfactant in the field of hydrophobic coatings comprises the following steps:

[0066] In the first step, the substrate was immersed in the supramolecular aggregate surfactant and stirred continuously for 2 hours. The contact angle test of the substrate without hydrophobic treatment is shown in the figure below. Figure 3 As shown, the contact angle is 73.3°;

[0067] In the second step, the substrate is taken out and placed in a forced air oven for 2 hours to dry the substrate to obtain a supramolecular aggregate surfactant-modified material. Figure 4 SEM image of the lotus leaf-like structure on the substrate surface after surface modification with an active agent in Example 1. Figure 5 The contact angle test of the substrate after surface modification by the active agent in Example 1 is shown in FIG. Figure 4 It can be seen that the surface of the substrate after surface modification by the active agent in Example 1 has a lotus leaf-like structure. Figure 5 It can be seen that the contact angle of Example 1 is 147.6°, indicating that Example 1 has good hydrophobicity;

[0068] Example 2

[0069] A method for preparing an adhesive ligand, comprising the following steps:

[0070] The first step is to add 0.05 mol of malonic acid into a beaker, dissolve it in 20 ml of toluene, and stir evenly to prepare a toluene solution of malonic acid.

[0071] In the second step, 0.1 mol of 4-hydroxypyridine-2,6-dicarboxylic acid was added to a beaker, dissolved in 20 ml of toluene, and stirred evenly to obtain a toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid. The toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid was then transferred to a three-necked flask.

[0072] In the third step, the malonic acid toluene solution obtained in the first step is transferred into a constant pressure separatory funnel and assembled with the three-necked flask in the second step.

[0073] Step 4: Add 10 ml of cyclohexane to the three-necked flask and heat to 110°C for 4 hours. During the reaction, keep one port open to facilitate the discharge of the mixed vapor of cyclohexane and water, and add 7 ml of cyclohexane every hour.

[0074] Step 5: Observe the flask for bubbling. If so, continue heating at 110°C until no more bubbles are produced.

[0075] In the sixth step, the solution obtained in the fifth step is transferred out and placed in a vacuum oven, and dried at 95° C. for 5 hours to obtain a bonding ligand.

[0076] A method for preparing a supramolecular aggregate surfactant comprises the following steps:

[0077] In the first step, the adhesive ligand is configured into a 25 mmol / L anhydrous ethanol solution, lanthanum chloride is configured into a 25 mmol / L anhydrous ethanol solution, and perfluorooctanoic acid is configured into a 25 mmol / L anhydrous ethanol solution as the coordination raw materials of the supramolecular aggregate surfactant.

[0078] In the second step, 10 ml of lanthanum chloride solution, 30 ml of binding ligand solution, and 50 ml of perfluorooctanoic acid solution were added to a beaker. Then, 10 ml of anhydrous ethanol was added, stirred for 20 minutes, and allowed to stand for 10 minutes to obtain a supramolecular aggregate surfactant.

[0079] An application of a supramolecular aggregate surfactant in the field of hydrophobic coatings comprises the following steps:

[0080] In the first step, the substrate was immersed in the supramolecular aggregate surfactant and stirred continuously for 2 hours. The contact angle test of the substrate without hydrophobic treatment is shown in the figure below. Figure 3 As shown, the contact angle is 73.3°;

[0081] In the second step, the substrate is taken out and placed in a forced air oven for 2 hours to dry the substrate to obtain a supramolecular aggregate surfactant-modified material. Figure 6 Example 2: SEM image of the lotus leaf-like structure on the substrate surface after surface modification with an active agent. Figure 7 The contact angle test of the substrate after surface modification by the active agent in Example 2 is shown in FIG. Figure 6 It can be seen that the surface of the substrate modified by the active agent in Example 2 has a lotus leaf structure. Figure 7 It can be seen that the contact angle of the substrate of Example 2 after surface modification with the active agent is 145.1°, indicating that Example 2 has good hydrophobicity.

[0082] A supramolecular aggregate surfactant is used as a solubilizer, comprising the following steps:

[0083] In the first step, 0.1 g of perfluorodecanol was placed in a beaker containing 20 ml of distilled water and stirred for 1 hour without dissolving.

[0084] In the second step, 10 ml of the supramolecular aggregate surfactant was added to the beaker and stirred for 1 hour. The perfluorodecanol was observed to dissolve. Because the solubilization effect of the surfactant was nearly identical across the formulation range, only Example 2 was analyzed for solubilization effect. This does not imply that other formulations within this range lacked solubilization effects.

[0085] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A supramolecular aggregate surfactant, characterized in that: The supramolecular aggregate surfactant comprises an adhesive ligand, perfluorooctanoic acid, a lanthanum chloride cross-linking agent and anhydrous ethanol; The adhesive ligand, perfluorooctanoic acid and lanthanum chloride crosslinker self-assemble into micelles and are dispersed in anhydrous ethanol; The ratio of the lanthanum chloride crosslinker, the adhesive ligand, perfluorooctanoic acid, and anhydrous ethanol is 1 mmol: 3-5 mmol: 4-5 mmol: 100 ml; The preparation method of the adhesive ligand is as follows: A toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid and a toluene solution of malonic acid are mixed and reacted in cyclohexane as a water agent. After the reaction, the filtrate is dried in a vacuum oven at 85-95° C. for 4.5-5.5 hours to obtain a sticky ligand.

2. A supramolecular aggregate surfactant according to claim 1, characterized in that: In the toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid, the ratio of 4-hydroxypyridine-2,6-dicarboxylic acid to toluene is 0.1 mol:20-30 ml; In the toluene solution of malonic acid, the ratio of malonic acid to toluene is 0.05 mol:20-30 ml; The volume ratio of the cyclohexane water-carrying agent to the total amount of toluene is 4:5, and the total amount of toluene refers to the volume sum of the toluene in the toluene solution of 4-hydroxypyridine-2,6-dicarboxylic acid and the toluene in the toluene solution of malonic acid; The molar ratio of the 4-hydroxypyridine-2,6-dicarboxylic acid to malonic acid is 2:

1.

3. The supramolecular aggregate surfactant according to claim 1, wherein: The reaction temperature is 100-120°C and the reaction time is 4-5h.

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