Composite super-hydrophobic material containing caffeine and derivatives thereof and preparation method of composite super-hydrophobic material

Abstract

The invention discloses a composite super-hydrophobic material containing caffeine and derivatives thereof and a preparation method of the composite super-hydrophobic material. A composite super-hydrophobic material containing caffeine and a caffeine derivative comprises a nanometer material, a low surface energy modifier, a solvent, an adhesive, and caffeine or a caffeine derivative, and the caffeine derivative is selected from one or more of a caffeine silane derivative and a caffeine fluorocarbon derivative. The caffeine and the derivative thereof are compounded with the super-hydrophobic material for the first time, the physical barrier effect of the super-hydrophobic surface and the chemical and biological repelling effect of the caffeine cooperate with each other, double active protection of physical and chemical is achieved, and the biological adhesion prevention and antibacterial performance is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, and in particular to a composite superhydrophobic material containing caffeine and its derivatives and its preparation method. Background Technology

[0002] Superhydrophobic materials, due to their unique water-repellent and self-cleaning properties, have shown broad application prospects in many fields. However, traditional superhydrophobic materials mainly rely on their physical topology to prevent wetting and contaminant adhesion. Their protective effect against the active attachment of marine organisms such as barnacles, shellfish, algae, and bacteria is often limited and not durable. Especially against organisms with strong adhesive properties, once their secreted mucus penetrates the air pad and contacts the substrate, they can firmly adhere to it.

[0003] Taking marine antifouling coatings as an example, existing technologies mostly use bactericides such as cuprous oxide and organotin compounds. However, these substances cause serious harm to the marine ecological environment and human health, and their use has been restricted or banned by international conventions. Therefore, the development of environmentally friendly, efficient, and multifunctional superhydrophobic materials has become an urgent need.

[0004] Caffeine, as a natural alkaloid, has been shown to have repellent and inhibitory effects on marine larvae and various bacteria. However, how to stably and sustainably integrate caffeine into superhydrophobic coatings and produce a synergistic enhancement effect has not been reported in existing technologies. Summary of the Invention

[0005] This invention solves the problems existing in the prior art and provides a composite superhydrophobic material containing caffeine and its derivatives and its preparation method. This invention is the first to combine caffeine and its derivatives with superhydrophobic materials. The physical barrier effect of the superhydrophobic surface and the chemical and biological repellency effect of caffeine work together to achieve dual active protection of "physical + chemical", which significantly improves the anti-bioadhesion and antibacterial properties.

[0006] The first objective of this invention is to provide a composite superhydrophobic material containing caffeine and its derivatives, comprising nanomaterials, a low surface energy modifier, a solvent, an adhesive, caffeine or a caffeine derivative, wherein the caffeine derivative is selected from one or more of caffeine silane derivatives and caffeine fluorocarbon derivatives, and the caffeine silane derivative is a compound represented by formula (I):

[0007] Wherein, R is a C1-C4 alkyl group, and n is an integer from 1 to 6;

[0008] The caffeine fluorocarbon derivative mentioned above is a compound represented by formula (II):

[0009] Where n is an integer from 1 to 13, and the linking group X is a chemical bond or a C1-C6 alkylene group.

[0010] Preferably, the composite superhydrophobic material containing caffeine and its derivatives comprises, by mass parts, 10-30 parts of nanomaterials, 0.5-2.0 parts of low surface energy modifier, 70-85.5 parts of solvent, 0.5-5 parts of adhesive, and 0.01-5 parts of caffeine or caffeine derivatives.

[0011] Further preferably, the composite superhydrophobic material containing caffeine and its derivatives comprises, by mass parts, 15-20 parts of nanomaterials, 1.5-2.0 parts of low surface energy modifier, 76-79 parts of solvent, 2-3 parts of adhesive, and 0.5-1.0 parts of caffeine or caffeine derivatives.

[0012] Preferably, the caffeine silane derivative is 9-(3-triethoxysilylpropyl)-caffeine, with the following structural formula:

[0013] The preparation method is as follows: under the protection of an inert gas, caffeine is dissolved in an anhydrous polar aprotic solvent, a strong base is slowly added under the cooling of an ice-water bath, and (3-chloropropyl)triethoxysilane is slowly added dropwise after stirring. The reaction is carried out at 20°C-80°C for 15-20 hours. After the reaction is completed, the reaction is quenched, concentrated and purified to obtain the target product 9-(3-triethoxysilylpropyl)-caffeine.

[0014] Further optimization involved dissolving caffeine in anhydrous N,N-dimethylformamide under an inert gas atmosphere, with a caffeine molar concentration of 0.1-0.5 mol / L. Sodium hydride was slowly added under ice-water bath cooling, with a caffeine to sodium hydride molar ratio of 1:1.0-1.5. After stirring, (3-chloropropyl)triethoxysilane was slowly added dropwise, with a caffeine to (3-chloropropyl)triethoxysilane molar ratio of 1:1.0-1.2. The reaction was carried out at 60°C for 16 hours. After the reaction was completed, the reaction was quenched, concentrated, and purified to obtain the target product 9-(3-triethoxysilylpropyl)-caffeine.

[0015] Further optimization involves adding sodium hydride at a caffeine molar concentration of 0.33 mol / L under ice-water bath cooling, with a caffeine to sodium hydride molar ratio of 1:1.2. After stirring, (3-chloropropyl)triethoxysilane is slowly added dropwise, with a caffeine to (3-chloropropyl)triethoxysilane molar ratio of 1:1.1.

[0016] Preferably, the caffeine fluorocarbon derivative is 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine, with the following structural formula;

[0017] The preparation method is as follows: under inert gas protection, caffeine is dissolved in an anhydrous polar aprotic solvent, a strong base is added under ice-water bath cooling, and 1H,1H,2H,2H-perfluorooctyl iodine is slowly added dropwise after stirring. The reaction is carried out at 60°C-80°C. After the reaction is completed, the reaction is quenched, concentrated and purified to obtain the target product 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine.

[0018] Further optimization involved dissolving caffeine in anhydrous N,N-dimethylformamide at a molar concentration of 0.1-0.5 mol / L, adding sodium hydride under ice-water bath cooling at a molar ratio of caffeine to sodium hydride of 1:1.0-1.5, stirring, and then slowly adding 1H,1H,2H,2H-perfluorooctyl iodine at a molar ratio of 1:0.9-1.1. The reaction was carried out at 60°C-80°C for 18-22 hours. After the reaction was completed, the mixture was quenched, concentrated, and purified to obtain the target product 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine.

[0019] Further optimization involved adding sodium hydride to a caffeine concentration of 0.25 mol / L under ice-water bath cooling, with a caffeine to sodium hydride molar ratio of 1:1.2. After stirring, 1H,1H,2H,2H-perfluorooctyl iodide was slowly added dropwise, with a caffeine to 1H,1H,2H,2H-perfluorooctyl iodide molar ratio of 1:1. The reaction was carried out at 70°C for 20 hours.

[0020] Preferably, the low surface energy modifier is a silane coupling agent represented by the general formula R'-Si-Y; wherein R' is a C3-C30 alkyl group or a C3-C30 perfluoroalkyl group, and Y is a hydrolyzable group.

[0021] Further preferably, the low surface energy modifier is heptadecafluorodecyltrimethoxysilane or octadecyltrimethoxysilane.

[0022] Preferably, the adhesive is selected from one or more of epoxy resin, silicone, polyurethane, acrylic resin, and trialdehyde resin.

[0023] More preferably, the adhesive is a hydroxyl-terminated polydimethylsiloxane or a fluorinated acrylate resin.

[0024] Preferably, the nanomaterial is an inorganic nanoparticle used to construct micro / nano rough structures.

[0025] Further preferably, the nanomaterial is nano-SiO2 or nano-ZnO.

[0026] Preferably, the solvent is water, ethanol, acetone, ethyl acetate, or N,N-dimethylformamide.

[0027] This invention also protects a method for preparing the composite superhydrophobic material containing caffeine and its derivatives, comprising the following steps: dispersing nanomaterials, low surface energy modifiers, adhesives, caffeine or caffeine derivatives sequentially in a solvent according to the above-mentioned mass proportions, mixing and stirring evenly to obtain the composite superhydrophobic material.

[0028] A composite superhydrophobic material is applied to the surface of a substrate and cured to obtain a composite superhydrophobic coating.

[0029] Preferably, the curing conditions are: curing at 70°C-90°C for 0.5-1.5 hours.

[0030] Further optimization resulted in the following curing conditions: curing at 80°C for 1 hour.

[0031] This invention also protects the application of the composite superhydrophobic material containing caffeine and its derivatives in the fields of marine antifouling, antibacterial surfaces, medical devices, food packaging, or air conditioning heat exchangers.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] 1. Synergistic effect: This invention is the first to combine caffeine and its derivatives with superhydrophobic materials. The physical barrier effect of the superhydrophobic surface and the chemical and biological repellency effect of caffeine work together to achieve dual active protection of "physical + chemical", which significantly improves the anti-bioadhesion and antibacterial performance.

[0034] 2. Green and environmentally friendly: Caffeine, as a natural and biodegradable substance, replaces traditional toxic antifouling agents such as heavy metals and organotin compounds, making it environmentally friendly.

[0035] 3. Long-lasting effect: The micro-nano porous structure of superhydrophobic materials can act as a reservoir for caffeine, enabling the slow and controlled release of caffeine, thereby extending the effective working time of the coating.

[0036] 4. Multifunctionality: The material provided by this invention has multiple functions such as superhydrophobicity, self-cleaning, anti-bioadhesion, antibacterial and antioxidant properties, and has a wide range of applications. Attached Figure Description

[0037] Figure 1 This is the infrared spectrum of 9-(3-triethoxysilylpropyl)-caffeine synthesized in Example 1 of this invention;

[0038] Figure 2 The infrared spectrum of 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine synthesized in Example 2 of this invention is shown.

[0039] Figure 3 This is a photograph of the water contact angle of the superhydrophobic coating in Embodiment 3 of the present invention;

[0040] Figure 4 This is a photograph of the water contact angle of the superhydrophobic coating in Embodiment 4 of the present invention;

[0041] Figure 5 This is a photograph of the water contact angle of the superhydrophobic coating in Embodiment 5 of the present invention;

[0042] Figure 6 This is a photograph of the water contact angle of the superhydrophobic coating in Embodiment 6 of the present invention;

[0043] Figure 7 This is a photograph of the water contact angle of the superhydrophobic coating in Embodiment 7 of the present invention. Detailed Implementation

[0044] The following embodiments are further illustrations of the present invention, but not limitations thereof.

[0045] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention. Unless otherwise specified, the experimental materials and reagents used herein are commercially available products conventionally available in this technical field.

[0046] Example 1: Synthesis of 9-(3-triethoxysilylpropyl)-caffeine

[0047] Experimental Procedure: Under a nitrogen atmosphere, caffeine (3.88 g, 20.0 mmol) and anhydrous N,N-dimethylformamide (60 mL) were added to a 250 mL dry three-necked flask equipped with a magnetic stir bar, a reflux condenser, and a constant-pressure dropping funnel. The system was cooled in an ice-water bath, and sodium hydride (0.96 g, 60% dispersed in mineral oil, 24.0 mmol) was slowly added in portions with stirring. After the addition was complete, the ice bath was removed, and the mixture was stirred at room temperature for 60 minutes, during which a large number of bubbles were generated.

[0048] Subsequently, (3-chloropropyl)triethoxysilane (5.38 mL, 22.0 mmol) was slowly added dropwise through a constant-pressure dropping funnel. After the addition was complete, the reaction system was heated to 60°C and stirred at this temperature for 16 hours. The reaction progress was monitored by TLC (thin-layer chromatography, developing solvent: dichloromethane / methanol = 10:1).

[0049] After the reaction was complete, the system was cooled to 0°C, and methanol (5 mL) was carefully added dropwise to quench excess sodium hydride. The reaction solution was transferred to a rotary evaporator and concentrated under reduced pressure in a 50°C water bath to remove most of the DMF. The crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate, from 2:1 to 1:1). The target fraction was collected and rotary evaporated to give 9-(3-triethoxysilylpropyl)-caffeine as a pale yellow viscous liquid (6.52 g, 85% yield).

[0050] Infrared testing and characterization, such as Figure 1 As shown, the peak at 1700 cm⁻¹ is the C=O peak of caffeine, and the peak at 1100 cm⁻¹ is the Si-OC peak, indicating that the target product 9-(3-triethoxysilylpropyl)-caffeine was successfully synthesized.

[0051] Example 2: Synthesis of 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine

[0052] Experimental procedure: Following the apparatus and starting procedure of Example 1, caffeine (1.94 g, 10.0 mmol) was dissolved in anhydrous DMF (40 mL), and sodium hydride (0.48 g, 12.0 mmol) was added under the protection of an ice-water bath and nitrogen, and stirred at room temperature for 30 minutes.

[0053] Subsequently, 1H,1H,2H,2H-perfluorooctyl iodide (5.36 g, 10.0 mmol) dissolved in 10 mL of anhydrous DMF was slowly added dropwise. After the addition was complete, the reaction system was heated to 70°C and stirred for 20 hours. The reaction was monitored by TLC (electrolyte: petroleum ether / ethyl acetate = 3:1).

[0054] After cooling, the reaction was carefully quenched. The reaction solution was poured into 200 mL of ice water, and a white solid precipitated. Extraction was performed with dichloromethane (3 × 50 mL), the organic phases were combined, washed with saturated brine, and dried over anhydrous magnesium sulfate. After filtration and concentration, the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 4:1) to give 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine as a white solid (5.01 g, 78% yield).

[0055] Infrared testing and characterization, such as Figure 2 As shown, the C=O peak of caffeine is at 1700 cm⁻¹, and the CF absorption band is in the 1200-1140 cm⁻¹ region, indicating that the target product 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine was successfully synthesized.

[0056] Example 3: Preparation and performance testing of composite superhydrophobic materials (caffeine silane derivatives)

[0057] Material preparation: Components (parts by mass): 15 parts nano SiO2; 2 parts low surface energy modifier (heptadecyltrimethoxysilane); 3 parts adhesive (hydroxyl-terminated polydimethylsiloxane); 1 part caffeine silane derivative synthesized in Example 1; 79 parts solvent (ethyl acetate).

[0058] Preparation method: Add all the above components to a beaker and stir magnetically for 2 hours until they are mixed evenly to obtain a white, uniformly dispersed composite superhydrophobic coating.

[0059] Coating preparation and performance testing:

[0060] The above coating was applied to a clean glass substrate by spraying and cured at 80°C for 1 hour to form a superhydrophobic coating.

[0061] Hydrophobicity test: Measured using a contact angle meter, the water contact angle is 160° and the roll-off angle is 4°; Figure 3 The image shown is a photograph of the water contact angle.

[0062] Biofouling resistance test: After immersing in seawater rich in algae for 30 days, almost no algae adhered to the surface, with an algae resistance rate of 95%. After immersing the coated sample in seawater rich in barnacle larvae for 30 days, almost no barnacles adhered to the surface, with a barnacle resistance rate of 95%.

[0063] Antibacterial test: The coating was tested separately against Escherichia coli, Staphylococcus aureus, and Vibrio vulnificus. 6 The bacterial suspension was co-cultured with CFU / mL for 24 h, then washed three times with buffer, and the number of bacterial colonies was tested. The test results showed that the antibacterial rate of the coating against the above bacterial species was greater than 99%.

[0064] Example 4: Preparation and performance testing of composite superhydrophobic materials (caffeine fluorocarbon derivatives)

[0065] Material preparation: Components (parts by mass): Nano ZnO: 20 parts, Low surface energy modifier (octadecyltrimethoxysilane): 1.5 parts, Adhesive (fluorinated acrylate resin): 2 parts, Caffeine fluorocarbon derivative synthesized in Example 2: 0.5 parts, Solvent (acetone): 76 parts.

[0066] Preparation method: Same as in Example 3.

[0067] Coating preparation: Same as in Example 3.

[0068] Coating performance:

[0069] Hydrophobicity: Water contact angle is 162°, roll-off angle is 2°; Figure 4The image shown is a photograph of the water contact angle.

[0070] Anti-biofouling test: After immersing in seawater rich in algae for 30 days, almost no algae adhered to the surface, with an anti-algae adhesion rate of 95%. After immersing the coated sample in seawater rich in barnacle larvae for 30 days, almost no barnacles adhered to the surface, with an anti-barnacle adhesion rate of 95%.

[0071] Antibacterial test: The coating was tested separately against Escherichia coli, Staphylococcus aureus, and Vibrio vulnificus. 6 The bacterial suspension was co-cultured with CFU / mL for 24 h, then washed three times with buffer, and the number of bacterial colonies was tested. The test results showed that the antibacterial rate of the coating against the above bacterial species was greater than 99%.

[0072] Example 5: Preparation and Performance Testing of Composite Superhydrophobic Materials (Caffeine)

[0073] Material preparation: Components (parts by mass): Nano ZnO: 20 parts, Low surface energy modifier (octadecyltrimethoxysilane): 1.5 parts, Adhesive (fluorinated acrylate resin): 2 parts, Caffeine: 0.5 parts, Solvent (acetone): 76 parts.

[0074] Preparation method: Same as in Example 3.

[0075] Coating performance:

[0076] Hydrophobicity: Water contact angle is 158°, roll-off angle is 2°; Figure 5 The image shown is a photograph of the water contact angle.

[0077] Biofouling resistance test: After immersing in seawater rich in algae for 30 days, almost no algae adhered to the surface, with an algae resistance rate of 95%. After immersing the coated sample in seawater rich in barnacle larvae for 30 days, almost no barnacles adhered to the surface, with a barnacle resistance rate of 95%.

[0078] Antibacterial test: The coating was tested against Escherichia coli, Staphylococcus aureus and Vibrio vulnificus. The coating was co-cultured with bacterial suspension of 1×106 CFU / ml for 24 h and then washed 3 times with buffer. The number of bacterial colonies was tested. The test results showed that the antibacterial rate of the coating against the above bacterial species was greater than 99%.

[0079] Example 6

[0080] Similar to Example 4, except that 0.5 parts of the caffeine fluorocarbon derivative synthesized in Example 2 are replaced with 0.25 parts of the caffeine fluorocarbon derivative synthesized in Example 2 and 0.25 parts of caffeine.

[0081] Coating performance:

[0082] Hydrophobicity: Water contact angle is 165°, roll-off angle is 2°; Figure 6 The image shown is a photograph of the water contact angle.

[0083] Biofouling resistance test: After immersing in seawater rich in algae for 30 days, almost no algae adhered to the surface, with an algae resistance rate of 95%. After immersing the coated sample in seawater rich in barnacle larvae for 30 days, almost no barnacles adhered to the surface, with a barnacle resistance rate of 95%.

[0084] Antibacterial test: The coating was tested against Escherichia coli, Staphylococcus aureus and Vibrio vulnificus. The coating was co-cultured with bacterial suspension of 1×106 CFU / ml for 24 h and then washed 3 times with buffer. The number of bacterial colonies was tested. The test results showed that the antibacterial rate of the coating against the above bacterial species was greater than 99%.

[0085] Example 7

[0086] Same as Example 4, except that 0.5 parts of the caffeine fluorocarbon derivative synthesized in Example 2 are replaced with 0.5 parts of the caffeine silane derivative synthesized in Example 1.

[0087] Coating performance:

[0088] Hydrophobicity: Water contact angle is 165°, roll-off angle is 2°; Figure 7 The image shown is a photograph of the water contact angle.

[0089] Biofouling resistance test: After immersing in seawater rich in algae for 30 days, almost no algae adhered to the surface, with an algae resistance rate of 95%. After immersing the coated sample in seawater rich in barnacle larvae for 30 days, almost no barnacles adhered to the surface, with a barnacle resistance rate of 95%.

[0090] Antibacterial test: The coating was tested against Escherichia coli, Staphylococcus aureus and Vibrio vulnificus. The coating was co-cultured with bacterial suspension of 1×106 CFU / ml for 24 h and then washed 3 times with buffer. The number of bacterial colonies was tested. The test results showed that the antibacterial rate of the coating against the above bacterial species was greater than 99%.

[0091] Comparative Example 1

[0092] Similar to Example 5, except that no bioactive antifouling agent (caffeine) is added, while the remaining components and preparation method are exactly the same.

[0093] Results: The coating initially exhibited good hydrophobicity (contact angle 152°), but its performance was significantly inferior to the above-mentioned embodiments in marine biofouling and antibacterial tests. Barnacles and algae attachment were severe, with anti-algae and anti-barnacle attachment rates below 10% and antibacterial rates below 10%.

[0094] The test results of Examples 3-7 and Comparative Example 1 are shown in Table 1:

[0095] Table 1

[0096] Example 8

[0097] Same as Example 4, except that: the composite superhydrophobic material, by mass parts, includes 10 parts of nanomaterial, 1.5 parts of low surface energy modifier, 70 parts of solvent, 0.5 parts of adhesive, and 0.01 parts of caffeine fluorocarbon derivative synthesized in Example 2.

[0098] Add all the above components to a beaker and stir magnetically for 2 hours until uniformly mixed to obtain a white, uniformly dispersed composite superhydrophobic coating. Apply the coating to a clean glass substrate by spraying and cure at 70°C for 1.5 hours to form a superhydrophobic coating.

[0099] Example 9

[0100] Same as Example 4, except that: the composite superhydrophobic material, by mass parts, includes 30 parts of nanomaterial, 2 parts of low surface energy modifier, 85.5 parts of solvent, 5 parts of adhesive, and 5 parts of caffeine fluorocarbon derivative synthesized in Example 2.

[0101] Add all the above components to a beaker and stir magnetically for 2 hours until uniformly mixed to obtain a white, uniformly dispersed composite superhydrophobic coating. Apply the coating to a clean glass substrate by spraying and cure at 90°C for 0.5 hours to form a superhydrophobic coating.

[0102] The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of ​​the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A composite superhydrophobic material containing caffeine and its derivatives, characterized in that, The components include nanomaterials, low surface energy modifiers, solvents, adhesives, caffeine, or caffeine derivatives, wherein the caffeine derivative is selected from one or more of caffeine silane derivatives and caffeine fluorocarbon derivatives, and the caffeine silane derivative is a compound represented by formula (I): ； Wherein, R is a C1-C4 alkyl group, and n is an integer from 1 to 6; The caffeine fluorocarbon derivative mentioned above is a compound represented by formula (II): ； Where n is an integer from 1 to 13, and the linking group X is a chemical bond or a C1-C6 alkylene group.

2. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1, characterized in that, By mass, it includes 10-30 parts of nanomaterials, 0.5-2.0 parts of low surface energy modifier, 70-85.5 parts of solvent, 0.5-5 parts of adhesive, and 0.01-5 parts of caffeine or caffeine derivatives.

3. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The caffeine silane derivative mentioned is 9-(3-triethoxysilylpropyl)-caffeine, and its structural formula is as follows: ； The preparation method is as follows: under the protection of an inert gas, caffeine is dissolved in an anhydrous polar aprotic solvent, a strong base is slowly added under the cooling of an ice-water bath, and (3-chloropropyl)triethoxysilane is slowly added dropwise after stirring. The reaction is carried out at 20°C-80°C for 15-20 hours. After the reaction is completed, the reaction is quenched, concentrated and purified to obtain the target product 9-(3-triethoxysilylpropyl)-caffeine.

4. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The caffeine fluorocarbon derivative is 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine, and its structural formula is as follows; ； The preparation method is as follows: under inert gas protection, caffeine is dissolved in an anhydrous polar aprotic solvent, a strong base is added under ice-water bath cooling, and 1H,1H,2H,2H-perfluorooctyl iodine is slowly added dropwise after stirring. The reaction is carried out at 60°C-80°C. After the reaction is completed, the reaction is quenched, concentrated and purified to obtain the target product 9-(1H,1H,2H,2H-perfluorooctyl)-caffeine.

5. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The low surface energy modifier is a silane coupling agent represented by the general formula R'-Si-Y; wherein R' is a C3-C30 alkyl group or a C3-C30 perfluoroalkyl group, and Y is a hydrolyzable group.

6. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The adhesive is selected from one or more of epoxy resin, silicone, polyurethane, acrylic resin, and trialdehyde resin.

7. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The nanomaterials mentioned are inorganic nanoparticles used to construct micro-nano rough structures.

8. The composite superhydrophobic material containing caffeine and its derivatives according to claim 1 or 2, characterized in that, The solvent is water, ethanol, acetone, ethyl acetate, or N,N-dimethylformamide.

9. The method for preparing the composite superhydrophobic material containing caffeine and its derivatives as described in claim 1 or 2, characterized in that, The process includes the following steps: dispersing nanomaterials, low surface energy modifiers, adhesives, and caffeine or caffeine derivatives sequentially in a solvent, mixing and stirring until homogeneous, to obtain a composite superhydrophobic material.

10. The application of the composite superhydrophobic material containing caffeine and its derivatives as described in claim 1 or 2 in the fields of marine antifouling, antibacterial surfaces, medical devices, food packaging, or air conditioning heat exchangers.

Images