Cardanol-based uv-curable hydrophobic stain repellent coating and method of making same

Abstract

The application discloses a preparation method of a cashew phenol-based ultraviolet light curing hydrophobic antifouling coating, and specifically comprises the following steps: step 1, preparing a cashew phenol-based ultraviolet light curing monomer; step 2, preparing a fluorine-containing hydroxyl acrylate polymer according to the product obtained in step 1; step 3, preparing a cashew phenol-based polyurethane acrylate coating according to the product obtained in step 2; and step 4, preparing a cashew phenol-based ultraviolet light curing coating by adding a photoinitiator to the product obtained in step 3. The application further discloses the cashew phenol-based ultraviolet light curing hydrophobic antifouling coating; and the coating prepared by the application has the characteristics of high hydrophobicity, high light transmittance and low pollution.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, and relates to a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol. This invention also relates to a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol. Background Technology

[0002] Ultraviolet (UV) curing technology uses UV light as the curing source to rapidly polymerize and crosslink the curable components. Compared to traditional thermosetting, which requires prolonged high-temperature curing and is unsuitable for heat-sensitive substrates, UV curing offers advantages such as high efficiency, low energy consumption, and no need for heating at room temperature. Furthermore, it does not release volatile organic compounds (VOCs) during the curing process, making it considered a "clean and green" curing technology. It has been widely applied in fields such as medical devices, digital electronics, aerospace, and instrumentation.

[0003] Cashew nut shell phenol is a common renewable biomass material. Due to its unsaturated long chains, benzene rings, and hydroxyl groups, cashew nut shell phenol possesses excellent flexibility, hydrophobicity, and heat resistance. Numerous studies have been conducted on the use of cashew nut shell phenol and its derivatives in UV-cured coatings. However, research on the application of cashew nut shell phenol in UV-cured hydrophobic and antifouling coatings is scarce.

[0004] Furthermore, most current UV-curable coatings are prepared by adding inorganic nanoparticles or using large amounts of petroleum-based raw materials. While the addition of large amounts of inorganic nanoparticles increases hydrophobicity to some extent, it reduces the transparency of the coating; and the extensive use of petroleum-based raw materials will pollute the environment.

[0005] Therefore, in this field, it is desirable to develop photocurable coatings with high ultraviolet light transmittance and low pollution. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol, wherein the coating prepared by this method has the characteristics of high hydrophobicity, high light transmittance and low pollution.

[0007] Another object of the present invention is to provide a UV-curable hydrophobic and antifouling coating based on cashew nut shell.

[0008] The first technical solution adopted in this invention is a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, which specifically includes the following steps:

[0009] Step 1: Prepare cashew phenol-based UV-curable monomer;

[0010] Step 2: Prepare a fluorinated hydroxyl acrylate polymer based on the product obtained in Step 1;

[0011] Step 3: Prepare cashew phenol-based polyurethane acrylic coating based on the product obtained in Step 2;

[0012] Step 4: Add a photoinitiator to the product obtained in Step 3 to prepare a cashew phenol-based UV-curable coating.

[0013] The first technical solution of this invention is further characterized by:

[0014] The specific process of step 1 is as follows:

[0015] 4,4-diisocyanate dicyclohexylmethane, cashew nut shell phenol, hydroxyethyl acrylate, and solvent were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1:1 to 1:2.02:1:1. Under a nitrogen atmosphere, the reaction mixture was stirred at 400 rpm to 600 rpm and heated to 75°C to 85°C for 1 h to 3 h. The reaction was then stopped, and the unreacted solvent was removed by rotary evaporation at 30°C to 40°C for 5 min to 10 min to obtain cashew nut shell phenol-based UV-curable monomer.

[0016] The specific process of step 2 is as follows:

[0017] Cashew phenol-based UV-curable monomer, hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1 to 1:2.05:1. The mixture was stirred at 400 rpm to 600 rpm and heated to 80°C to 90°C under a nitrogen atmosphere and held at this temperature for 4 h to 6 h. The mixture was then rotary evaporated at 30°C to 40°C for 5 min to 10 min to obtain a fluorinated hydroxy acrylate polymer.

[0018] The specific process of step 3 is as follows:

[0019] Fluorinated hydroxy acrylate polymer, 4,4'-dicyclohexylmethane diisocyanate, and pentaerythritol triacrylate in a molar ratio of 1:1:1 to 1:1.05:1.05 were added to a three-necked round-bottom flask. The mixture was stirred at 400 rpm to 600 rpm and heated to 70°C to 80°C under a nitrogen atmosphere and kept at this temperature for 2 to 4 hours to obtain cashew phenol-based polyurethane acrylic coating.

[0020] In step 3, the structural formula of the cashew phenol-based polyurethane acrylic coating is:

[0021] .

[0022] The specific process of step 4 is as follows:

[0023] The cashew nut phenol-based polyurethane acrylic coating, photoinitiator, and solvent are mixed and stirred for 10 to 30 minutes. After standing to remove air bubbles, the mixture is applied to a glass substrate using a coater. Then, it is cured under UV irradiation for 100 to 150 seconds to obtain a cashew nut phenol-based UV-cured coating.

[0024] In step 4, the photoinitiator is any one or a combination of at least two of the following: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzophenone, 4-benzoyl-4-methyl-diphenyl sulfide, methyl 2-benzoylbenzoate, or ethyl 4-(N,N-dimethylamino)benzoate.

[0025] In steps 1 and 4, the solvent is any one or a combination of two of the following: ketone solvents or ether solvents.

[0026] The ketone solvent is any one or a combination of at least two of butanone, methyl isobutyl ketone, cyclopentanone, or isoflurane; the ether solvent is any one or a combination of two of propylene glycol methyl ether and propylene glycol methyl ether acetate.

[0027] The second technical solution adopted in this invention is a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, which is prepared by a UV-curable hydrophobic and antifouling coating preparation method based on cashew nut shell phenol.

[0028] The beneficial effects of this invention are as follows:

[0029] (1) Most coatings and polymers are produced from petroleum-based products, which will inevitably face shortages sooner or later. Cashew nut shell powder is a very important renewable resource. Using cashew nut shell powder to replace chemical raw materials in the preparation of UV-curable coatings can improve environmental friendliness and reduce costs.

[0030] (2) Most hydrophobic coatings incorporate nanoparticles. While this improves hydrophobicity, it sacrifices light transmittance to some extent. This invention utilizes the synergistic effect of cashew nut shell powder and fluorinated acrylic acid to prepare a UV-curable coating with good light transmittance, excellent hydrophobicity, self-cleaning properties, and anti-graffiti properties. The unique benzene ring structure in cashew nut shell powder can also improve the hardness of the coating to some extent.

[0031] (3) Fluorine atoms readily form HF bonds with polyurethane, which weakens hydrophobicity. The addition of the long hydrophobic chain of cashew phenol can break the HF bonds, causing more F atoms to be oriented on the surface, reducing the amount of fluorine used while improving hydrophobicity. Attached Figure Description

[0032] Figure 1 is a schematic diagram of the self-cleaning performance of the cashew phenol-based UV-curable coating obtained in Example 1 of the preparation method of the cashew phenol-based UV-curable coating of the present invention; wherein, Figure 1(a) is a schematic diagram of the self-cleaning performance of the uncoated cashew phenol-based UV-curable coating; Figure 1(b) is a schematic diagram of the self-cleaning performance of the cashew phenol-based UV-curable coating.

[0033] Figure 2 The infrared absorption spectrum of the cashew phenol-based ultraviolet-curable coating prepared in Example 1 of the preparation method of the cashew phenol-based ultraviolet-curable coating of the present invention is shown.

[0034] Figure 3 This is a water contact angle diagram of the cashew phenol-based UV-curable coating prepared in Example 1 of the preparation method of the UV-curable coating based on cashew phenol of the present invention.

[0035] Figure 4 This is a UV transmittance diagram of the UV-curable coating based on cashew phenol, prepared in Example 1 of the preparation method of the UV-curable hydrophobic and antifouling coating based on cashew phenol of the present invention. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0037] The present invention discloses a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, which specifically includes the following steps:

[0038] Step 1, preparing cashew phenol-based UV-curable monomers, specifically:

[0039] HMDI (4,4-diisocyanate dicyclohexylmethane), cashew nut shell powder, hydroxyethyl acrylate, and solvent were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1:1 to 1:2.02:1:1. Under a nitrogen atmosphere, the reaction mixture was stirred at 400 rpm to 600 rpm and heated to 75–85 °C for 1–3 h, after which the reaction was stopped. Unreacted solvent was removed by rotary evaporation at 30–40 °C for 5–10 min to obtain the cashew nut shell powder-based UV-curable monomer.

[0040] In this invention, cashew phenol contains unsaturated long chains, which gives it a certain degree of hydrophobicity. Cashew phenol is introduced into polyurethane acrylic acid to replace part of the fluorinated acrylic acid. The long chains in cashew phenol can break the HF bonds formed between fluorine atoms and polyurethane, allowing more fluorine atoms to migrate to the surface. At the same time, cashew phenol and fluorinated acrylic acid crosslink through photocuring reaction to form a tight coating. The hydrophobic effect of the coating is improved through synergistic effect.

[0041] Step 2: Prepare a fluorinated hydroxyl acrylate polymer based on the product obtained in Step 1, specifically as follows:

[0042] A molar ratio of cashew nut shell phenol-based UV-curable monomer (based on the monomer prepared in step 1), hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were sequentially added to a three-necked round-bottom flask. Under a nitrogen atmosphere, the mixture was stirred at 400 rpm to 600 rpm and heated to 80–90 °C for 4–6 h. The fluorinated hydroxy acrylate polymer was obtained by rotary evaporation at 30–40 °C for 5–10 min.

[0043] Step 3: Prepare a cashew phenol-based polyurethane acrylic coating based on the product obtained in Step 2, specifically as follows:

[0044] A fluorinated hydroxyl acrylate polymer (based on the one prepared in step 2), HMDI (4,4-diisocyanate dicyclohexylmethane), and pentaerythritol triacrylate (PETA) in a molar ratio of 1:1:1 to 1:1.05:1.05 were added to a three-necked round-bottom flask. Under a nitrogen atmosphere, the mixture was stirred at 400 rpm to 600 rpm and heated to 70 °C to 80 °C for 2 h to 4 h to obtain a cashew phenol-based polyurethane acrylic coating.

[0045] The structural formula of cashew phenol-based polyurethane acrylic coating is:

[0046] .

[0047] Where R2 represents free radical polymerization, and the product is a polymer. n1, n2, and n3 are the degrees of polymerization, which are the number of repeating units in the polymer and can take any value.

[0048] Step 4: Prepare a cashew nut shell phenol-based UV-curable coating by adding a photoinitiator to the product obtained in Step 3, specifically as follows:

[0049] The cashew nut shell phenol-based polyurethane acrylic coating (based on the one prepared in step 3) is mixed and stirred with a photoinitiator (4%–6% of the total mass of the cashew nut shell phenol-based polyurethane acrylic coating) and a solvent (10%–20% of the total mass of the cashew nut shell phenol-based polyurethane acrylic coating) for 10–30 min. After standing to remove air bubbles, the mixture is applied to a glass substrate using a coater and then cured under UV irradiation for 100–150 s before curing is stopped to obtain a cashew nut shell phenol-based UV-cured coating.

[0050] In this invention, the photoinitiator is any one or a combination of at least two of the following: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzophenone, 4-benzoyl-4-methyl-diphenyl sulfide, methyl 2-benzoylbenzoate, or ethyl 4-(N,N-dimethylamino)benzoate.

[0051] The photoinitiator is any one or a combination of at least two of the following: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzophenone, 4-benzoyl-4-methyl-diphenyl sulfide, methyl 2-benzoylbenzoate, or ethyl 4-(N,N-dimethylamino)benzoate.

[0052] In steps 1 and 4 above, the solvent is any one or a combination of two of ketone solvents or ether solvents. The ketone solvent is any one or a combination of at least two of butanone, methyl isobutyl ketone, cyclopentanone, or isoflurane; the ether solvent is any one or a combination of two of propylene glycol methyl ether and propylene glycol methyl ether acetate.

[0053] In this invention, the amount of cashew phenol-based UV-curable coating should not be excessive. If too much of this component is used, the solid content will be too high, making it difficult to coat and form a film during use. If too little is used, the UV-curable coating will be too thin, making it impossible to coat and form a film during use.

[0054] Example 1

[0055] The present invention relates to a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, comprising the following steps:

[0056] Step 1, the preparation of cashew phenol-based UV-curable monomers, specifically involves:

[0057] HMDI (4,4-dicyclohexylmethane diisocyanate), cashew nut shell phenolate, hydroxyethyl acrylate, and butanone (solvent) were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1:1. Under a nitrogen atmosphere, the reaction mixture was stirred at 400 rpm and heated to 75°C for 1 h, after which the reaction was stopped. Unreacted butanone (solvent) was removed by rotary evaporation at 30°C for 5 min to obtain a cashew nut shell phenolate-based UV-curable monomer.

[0058] Step 2, the preparation of the fluorinated hydroxyl acrylate polymer, specifically involves:

[0059] Cashew nut shell phenol-based UV-curable monomer, hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1. Under a nitrogen atmosphere, the mixture was stirred at 400 rpm and heated to 80 °C for 4 h. The fluorinated hydroxy acrylate polymer was then obtained by rotary evaporation at 30 °C for 5 min.

[0060] Step 3, the preparation of cashew phenol-based polyurethane acrylic coating, specifically involves:

[0061] Fluorinated hydroxyl acrylate polymer, HMDI (4,4-diisocyanate dicyclohexylmethane), and pentaerythritol triacrylate (PETA) were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:1:1. The mixture was stirred at 400 rpm and heated to 70 °C for 2 h under a nitrogen atmosphere to obtain a cashew phenol-based polyurethane acrylic coating.

[0062] The structure of the cashew phenol-based polyurethane acrylic coating is shown below:

[0063]

[0064] Step 4, the preparation of the cashew phenol-based UV-curable coating, specifically involves:

[0065] The cashew nut phenol-based polyurethane acrylic coating, photoinitiator (4% of the total mass of the cashew nut phenol-based polyurethane acrylic coating), and solvent (10% of the total mass of the cashew nut phenol-based polyurethane acrylic coating) were mixed and stirred for 10 min. After standing to remove air bubbles, the mixture was applied to a glass substrate using a coater and then cured under UV irradiation for 100 s before stopping the curing process to obtain a cashew nut phenol-based UV-cured coating.

[0066] Figure 1 is a schematic diagram of the self-cleaning performance of the UV-cured hydrophobic and antifouling coating based on cashew nut shell phenol prepared in Example 1 of the present invention; wherein, Figure 1(a) is a schematic diagram of the self-cleaning performance of the UV-cured hydrophobic and antifouling coating without cashew nut shell phenol coating; Figure 1(b) is a schematic diagram of the self-cleaning performance of the UV-cured hydrophobic and antifouling coating with cashew nut shell phenol coating. As can be seen from Figure 1(a), on the uncoated glass surface, water droplets have difficulty carrying away clay when flowing down the glass surface; as can be seen from Figure 1(b), on the glass surface coated with the UV-cured film, water droplets can easily carry away clay during the sliding process. This demonstrates that the coating has good self-cleaning ability.

[0067] Figure 2 The image shows the infrared absorption spectrum of the UV-curable hydrophobic and antifouling coating based on cashew phenol prepared in Example 1 of this invention; as can be seen from the image, the coating exhibits high absorption at 2950, ​​2856, and 1739 cm⁻¹. -1Absorption peaks were observed at wavenumbers corresponding to the stretching vibration of CH3, the bending vibration of CH2, and the characteristic absorption peak of C=O in the ester group. (3303 cm⁻¹) -1 and 1640 cm -1 The absorption peaks indicate the successful preparation of the NH bond and the C=C double bond in the carbamate. Therefore, it can be concluded that the UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, prepared by the method disclosed in this invention, has been successfully synthesized.

[0068] Figure 3 The figure shows the water contact angle of the UV-cured hydrophobic and antifouling coating based on cashew nut shell phenol prepared in Example 1 of the present invention. As can be seen from the figure, the water contact angle of the UV-cured hydrophobic and antifouling coating based on cashew nut shell phenol reaches 125°, which meets the requirements for hydrophobicity and has good hydrophobicity.

[0069] See Figure 4 The image shows the ultraviolet light transmittance of the UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol prepared in Example 1 of this invention. As can be seen from the image, the transmittance of the UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol exceeds 90%, indicating good transparency.

[0070] Example 2

[0071] The present invention relates to a method for preparing a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol, comprising the following steps:

[0072] Step 1, the preparation of cashew phenol-based UV-curable monomers, specifically involves:

[0073] HMDI (4,4-diisocyanate dicyclohexylmethane), cashew nut shell powder, hydroxyethyl acrylate, and propylene glycol methyl ether (solvent) were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2.01:1:1. Under a nitrogen atmosphere, the reaction mixture was stirred at 500 rpm and heated to 80 °C for 2 h, after which the reaction was stopped. Unreacted propylene glycol methyl ether (solvent) was removed by rotary evaporation at 35 °C for 8 min to obtain the cashew nut shell powder-based UV-curable monomer.

[0074] Step 2, the preparation of the fluorinated hydroxyl acrylate polymer, specifically involves:

[0075] Cashew nut shell phenolate UV-curable monomer, hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2.02:1. Under a nitrogen atmosphere, the mixture was stirred at 500 rpm and heated to 85 °C for 5 h. The fluorinated hydroxy acrylate polymer was then obtained by rotary evaporation at 35 °C for 8 min.

[0076] Step 3, the preparation of cashew phenol-based polyurethane acrylic coating, specifically involves:

[0077] Fluorinated hydroxyl acrylate polymer, HMDI (4,4-diisocyanate dicyclohexylmethane), and pentaerythritol triacrylate (PETA) were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:1.02:1.02. The mixture was stirred at 500 rpm and heated to 75°C for 3 h under a nitrogen atmosphere to obtain a cashew phenol-based polyurethane acrylic coating.

[0078] The structure of the cashew phenol-based polyurethane acrylic coating is shown below:

[0079]

[0080] Step 4, the preparation of the cashew phenol-based UV-curable coating, specifically involves:

[0081] The cashew nut phenol-based polyurethane acrylic coating, photoinitiator (5% of the total mass of the cashew nut phenol-based polyurethane acrylic coating), and solvent (15% of the total mass of the cashew nut phenol-based polyurethane acrylic coating) were mixed and stirred for 20 min. After standing to remove air bubbles, the mixture was applied to a glass substrate using a coater and then cured under UV irradiation for 130 s before stopping the curing process to obtain a cashew nut phenol-based UV-cured coating.

[0082] Example 3

[0083] Step 1, the preparation of cashew phenol-based UV-curable monomers, specifically involves:

[0084] HMDI (4,4-dicyclohexylmethane diisocyanate), cashew nut shell powder, hydroxyethyl acrylate, and solvent (a mixture of cyclopentanone and propylene glycol methyl ether ethyl ester) in a molar ratio of 1:2.02:1:1 were added sequentially to a three-necked round-bottom flask. Under a nitrogen atmosphere, the reaction mixture was stirred at 600 rpm and heated to 85 °C for 3 h, after which the reaction was stopped. Unreacted solvent (a mixture of cyclopentanone and propylene glycol methyl ether ethyl ester) was removed by rotary evaporation at 40 °C for 10 min, yielding a cashew nut shell powder-based UV-curable monomer.

[0085] Step 2, the preparation of the fluorinated hydroxyl acrylate polymer, specifically involves:

[0086] Cashew nut shell phenol-based UV-curable monomer, hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2.05:1. Under a nitrogen atmosphere, the mixture was stirred at 600 rpm and heated to 90 °C for 6 h. The resulting polymer was obtained by rotary evaporation at 40 °C for 10 min.

[0087] Step 3, the preparation of cashew phenol-based polyurethane acrylic coating, specifically involves:

[0088] Fluorinated hydroxyl acrylate polymer, HMDI (4,4-diisocyanate dicyclohexylmethane), and pentaerythritol triacrylate (PETA) were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:1.05:1.05. The mixture was stirred at 600 rpm and heated to 80 °C for 4 h under a nitrogen atmosphere to obtain a cashew phenol-based polyurethane acrylic coating.

[0089] The structure of the cashew phenol-based polyurethane acrylic coating is shown below:

[0090]

[0091] Step 4, the preparation of the cashew phenol-based UV-curable coating, specifically involves:

[0092] The cashew nut phenol-based polyurethane acrylic coating, photoinitiator (6% of the total mass of the cashew nut phenol-based polyurethane acrylic coating), and solvent (20% of the total mass of the cashew nut phenol-based polyurethane acrylic coating) were mixed and stirred for 30 min. After vacuum drying to remove air bubbles, the mixture was applied to a glass substrate using a coater and then cured under UV irradiation for 150 s before stopping the curing process to obtain a cashew nut phenol-based UV-cured coating.

[0093] This invention provides a UV-curable hydrophobic and antifouling coating based on cashew nut shell phenol. The coating is prepared using cashew nut shell phenol, a renewable resource, significantly reducing the use of petroleum-based materials. Under photoinitiator and UV irradiation conditions, the cured film exhibits good hydrophobicity and excellent optical transparency. It also demonstrates good self-cleaning properties against dust. The UV-curable antifouling coating prepared by this invention has great potential for practical applications.

Claims

1. A method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol, characterized in that: Specifically, the steps include the following: Step 1: Preparation of cashew nut shell phenol-based UV-curable monomer; The specific process of Step 1 is as follows: 4,4-diisocyanate dicyclohexylmethane, cashew nut shell phenol, hydroxyethyl acrylate and solvent are added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1:1 to 1:2.02:1:

1. Under a nitrogen atmosphere, the reaction mixture is stirred at 400 rpm to 600 rpm and heated to 75℃ to 85℃ for 1 h to 3 h. The reaction is then stopped. Unreacted solvent is removed by rotary evaporation at 30℃ to 40℃ for 5 min to 10 min to obtain the cashew nut shell phenol-based UV-curable monomer. Step 2: Prepare a fluorinated hydroxyl acrylate polymer based on the product obtained in Step 1; the specific process of Step 2 is as follows: Cashew phenol-based UV-curable monomer, hydroxyethyl methacrylate, and 1H,1H,2H,2H-perfluorodecyl acrylate were added sequentially to a three-necked round-bottom flask in a molar ratio of 1:2:1 to 1:2.05:

1. The mixture was stirred at 400 rpm to 600 rpm and heated to 80°C to 90°C under a nitrogen atmosphere and held at that temperature for 4 h to 6 h. The mixture was then rotary evaporated at 30°C to 40°C for 5 min to 10 min to obtain a fluorinated hydroxy acrylate polymer. Step 3: Prepare a cashew nut phenol-based polyurethane acrylic coating based on the product obtained in Step 2; the specific process of Step 3 is as follows: Fluorinated hydroxy acrylate polymer, 4,4'-dicyclohexylmethane diisocyanate and pentaerythritol triacrylate in a molar ratio of 1:1:1 to 1:1.05:1.05 were added to a three-necked round-bottom flask. The mixture was stirred at 400 rpm to 600 rpm and heated to 70°C to 80°C under a nitrogen atmosphere and kept at this temperature for 2 to 4 hours to obtain cashew phenol-based polyurethane acrylic coating. Step 4: Add a photoinitiator to the product obtained in Step 3 to prepare a cashew phenol-based UV-curable coating.

2. The method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol according to claim 1, characterized in that: In step 3, the structural formula of the cashew phenol-based polyurethane acrylic coating is: 。 3. The method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol according to claim 1, characterized in that: The specific process of step 4 is as follows: The cashew nut phenol-based polyurethane acrylic coating, photoinitiator, and solvent are mixed and stirred for 10 to 30 minutes. After vacuum drying to remove air bubbles, the mixture is applied to a glass substrate using a coater. Then, it is cured under UV irradiation for 100 to 150 seconds to obtain a cashew nut phenol-based UV-cured coating.

4. The method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol according to claim 3, characterized in that: In step 4, the photoinitiator is any one or a combination of at least two of the following: 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, hydroxycyclohexanephenyl ketone, benzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, methyl 2-benzoylbenzoate, or ethyl 4-dimethylaminobenzoate.

5. The method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol according to claim 4, characterized in that: In steps 1 and 4, the solvent is any one or a combination of two of the following: ketone solvents or ether solvents.

6. The method for preparing a UV-curable hydrophobic and antifouling coating based on cashew phenol according to claim 5, characterized in that: The ketone solvent is any one or a combination of at least two of butanone, methyl isobutyl ketone, cyclopentanone, or isophorone; the ether solvent is any one or a combination of two of propylene glycol methyl ether and propylene glycol methyl ether acetate.

7. A UV-curable hydrophobic and antifouling coating based on cashew phenol, characterized in that: The coating was prepared using the UV-curable hydrophobic and antifouling coating preparation method based on cashew phenol as described in claims 1-6.

Images