A coating material, an anti-fog and anti-fouling coating having an array of surface microstructures based thereon, and a method of preparing the coating

Abstract

The application discloses a coating material, an antifog and antifouling coating with a surface microstructure array based on the coating material and a preparation method of the coating. Raw materials of the antifog and antifouling coating material include SBMA, TFEMA, BPA and a polymerization initiator; the preparation method of the coating comprises the following steps: S1), preparing a PDMS mold with a surface microstructure array: preparing single-layer silica balls, transferring the single-layer silica balls to a PDMS film surface, and obtaining the PDMS mold after washing away the silica balls; S2), synthesizing the coating material; S3), preparing a polymer coating: injecting a trifluoroethanol solution of the coating material into the PDMS mold and covering the PDMS mold with a base material, stripping the mold after ultraviolet curing, and obtaining the antifog and antifouling coating. The antifog and antifouling coating in the application has high transparency, strong adhesion, excellent antifog and antifouling performance, good biocompatibility, and certain application value on medical endoscopes.

Description

Technical Field

[0001] The present invention relates to the field of anti-fog and anti-fouling coatings, and in particular to the construction of an anti-fog and anti-fouling coating with a surface microstructure array and a preparation method of the coating. Background Art

[0002] The fogging problem of transparent materials not only affects their optical properties, but also causes economic losses and, in severe cases, safety hazards. Taking medical endoscopes as an example, medical endoscopes are widely used in clinical practice and are essential tools for fine internal and external surgical examinations and minimally invasive treatments. However, surface fogging and low visibility caused by differences in the internal and external environments of the human body and tissue protein contamination are major problems that hinder the smooth progress of examinations or operations. Traditional defogging methods include spraying anti-fog agents or using heating devices before surgery, but these measures have short anti-fog effects, anti-fog agents cause certain irritation to tissues, cannot alleviate internal bacterial or blood contamination, and preoperative preparations are time-consuming. Therefore, the development of dual-functional coatings with anti-fog and anti-fouling properties is of great significance.

[0003] Traditional anti-fog coatings are mainly divided into superhydrophilic coatings and superhydrophobic coatings. Superhydrophilic coatings form a uniform water film on their surface, effectively reducing light scattering and refraction, thereby achieving an anti-fog effect. Superhydrophilicity, while achieving hydrophilicity, also has potential water solubility, which affects the coating's long-term stability. Superhydrophobic coatings exhibit high water contact angles and low contact angle hysteresis in terms of wettability, allowing droplets to easily slide off the surface, thus providing a good anti-fog effect. However, the superhydrophobic properties of such coatings are difficult to maintain stably, and the preparation process is relatively complex. In addition, in recent years, amphiphilic anti-fog coatings have been prepared by simultaneously introducing hydrophobic and hydrophilic segments into polymers. These coatings exhibit strong hygroscopicity, hindering the formation of surface fog. In addition, the hydrophobic segments in the polymer can effectively reduce the water solubility of the coating, promoting the coating's stability and durability.

[0004] As medical devices implanted in the human body, endoscopes are susceptible to bacterial and microbial adhesion during use. Therefore, while preventing fogging, it is also necessary to mitigate microbial contamination of the mirror surface. In recent years, progress has been made in the development of anti-fog and anti-fouling coatings. For example, zwitterionic materials are often used in anti-fog and anti-fouling coatings. The balanced charge and strong hydration of zwitterionic materials give them excellent anti-fog properties and resistance to bacterial adhesion. Furthermore, recent studies have shown that physical interference with surface micro- and nanostructures can inhibit biofilm formation. Micro- and nanostructured surfaces primarily rely on their physical structure to control microbial adhesion or growth, providing a new research direction for the development of anti-fouling surfaces.

[0005] Currently, research on dual-function anti-fog and anti-fouling coatings with surface microstructures is limited. The impact of surface micro- and nanostructures on the wettability and anti-fog properties of amphiphilic polymers requires further investigation, as does the mechanism of action of micro- and nanostructures on microbial contamination. Furthermore, in actual use, strong adhesion between the coating and the substrate remains a key factor affecting the coating's service life. Summary of the Invention

[0006] In order to solve the problems existing in the background technology, the present invention provides a coating material, an anti-fog and anti-fouling coating with a surface microstructure array based on the coating, and a method for preparing the coating.

[0007] The technical solution adopted in the present invention is:

[0008] 1. A coating material

[0009] The coating material is prepared using the following raw materials in parts by weight: 1-20 parts of sulfobetaine methacrylate (SBMA), 0.01-2 parts of trifluoroethyl methacrylate (TFEMA), 0.05-0.2 parts of 4-acryloyloxybenzophenone (BPA), and 0.05-0.1 parts of a polymerization initiator.

[0010] Specifically, the polymerization initiator is azobisisobutyronitrile (AIBN).

[0011] Furthermore, the raw materials also include trifluoroethanol used as a reaction solvent, and the initial total mass concentration of the sulfobetaine methacrylate, trifluoroethyl methacrylate and 4-acryloyloxybenzophenone in trifluoroethanol is 5-20wt%.

[0012] Specifically, the structural formula of the coating material is as follows:

[0013]

[0014] Among them, x:y:z=1~20:0.01~2:0.05~0.2.

[0015] 2. Preparation method of the above coating material

[0016] The preparation method specifically comprises the following steps: dissolving sulfobetaine methacrylate, trifluoroethyl methacrylate, and 4-acryloyloxybenzophenone in trifluoroethanol, and uniformly mixing to obtain a colorless and transparent reaction stock solution, wherein the total mass concentration of all solutes (sulfobetaine methacrylate, trifluoroethyl methacrylate, and 4-acryloyloxybenzophenone) in the reaction stock solution is 5-20 wt %. Subsequently, adding azobisisobutyronitrile to the reaction stock solution, and causing a free radical polymerization reaction at 50-70° C. under an inert gas atmosphere to obtain a terpolymer after the reaction is completed.

[0017] The inert gas is any one of nitrogen, helium, neon, argon, krypton and radon, or a combination of two or more.

[0018] 3. Anti-fog and anti-fouling coating with surface microstructure array

[0019] The material of the anti-fog and anti-fouling coating is the above-mentioned coating material or the coating material obtained by the above-mentioned preparation method.

[0020] 4. Preparation method of the anti-fog and anti-fouling coating having a surface microstructure array

[0021] The preparation method specifically comprises the following steps:

[0022] S1) preparing a PDMS mold having a surface microstructure array: forming a monolayer of silica on a glass surface using a silica sphere solution, then transferring the monolayer of silica from the glass surface to a PDMS membrane surface using PDMS, and finally soaking and washing the PDMS membrane with a hydrofluoric acid solution to remove the monolayer of silica on the PDMS membrane surface, thereby obtaining a PDMS mold having a surface microstructure array;

[0023] The silica sphere solution has a nanometer-scale particle size, preferably 350 nm to 650 nm. The silica sphere solution is prepared using n-butanol as the solvent, with a mass concentration of 0.5 to 5 wt%. The silica spheres can be prepared using tetraethyl orthosilicate as the silicon source via the Stober method. The raw materials for the silica spheres include tetraethyl orthosilicate, anhydrous ethanol, aqueous ammonia, and deionized water; the volume ratios of tetraethyl orthosilicate, anhydrous ethanol, aqueous ammonia, and deionized water are 1 to 5 parts, 20 to 50 parts, 1 to 10 parts, and 5 to 10 parts, respectively.

[0024] In step S1), the process of forming a single layer of silica on the surface of the glass sheet using the silica ball solution is specifically as follows: according to the Langmuir-Blodgett (LB) method, a film is vertically drawn in water using the silica ball solution and the glass sheet at a drawing speed of 2-10 mm / min.

[0025] In step S1), the process of transferring the monolayer of silicon dioxide from the glass surface to the surface of the PDMS film using PDMS is specifically as follows: PDMS is mixed with a curing agent, poured onto the monolayer of silicon dioxide on the surface of the glass sheet, and the PDMS film is peeled off after curing at 30-60 ° C for 1-5 hours. Wherein, PDMS and curing agent are both commercially available products and can be obtained through conventional commercial channels. The ratio between the two can be determined according to the recommended mixing ratio in the technical data sheet or product manual provided by the manufacturer, and the average molecular weight of polydimethylsiloxane PDMS is preferably about 25,000. In an embodiment of the present invention, the mixing ratio of PDMS to curing agent is 10:1, and the average molecular weight of polydimethylsiloxane PDMS is about 25,000.

[0026] In step S1), the process of washing away the single layer of silicon dioxide on the surface of the PDMS membrane with a hydrofluoric acid solution is specifically as follows: the PDMS membrane with the single layer of silicon dioxide embedded on the surface is immersed in a hydrofluoric acid solution with a volume fraction of 0.5-5% for 1-10 minutes.

[0027] S2) preparing a polymer coating having a surface microstructure array: injecting a coating material solution into a PDMS mold and covering the mold with a substrate so that the side of the PDMS mold having the surface microstructure array contacts the surface of the substrate to be coated, and after UV curing for 5 to 40 minutes, peeling the PDMS mold from the substrate to obtain an anti-fog and anti-fouling coating having a surface microstructure array; the solvent of the coating material solution is trifluoroethanol, and the mass concentration of the coating material in the coating material solution is 10 to 20 wt%.

[0028] The substrate is a polymer-based transparent substrate, which specifically refers to a general polymer-based transparent substrate containing hydrocarbon chains (such as polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyethylene (PE), etc.).

[0029] In step S2), the benzophenone groups (hereinafter referred to as BP groups) in the coating material terpolymer undergo a step transition under UV light, covalently bonding to the hydrocarbon chains on the surface of the polymer-based transparent substrate. This not only forms a crosslinked network for the linear polymers, but also forms a covalent bond at the interface between the coating and the substrate, contributing to improved coating stability and enhanced adhesion.

[0030] The PDMS mold can be reused after being rinsed with anhydrous ethanol after use. Therefore, the preparation method further includes the following steps:

[0031] Step S3): After the PDMS mold peeled from the substrate is rinsed with anhydrous ethanol, the rinsed PDMS mold is recovered and the recovered PDMS mold is used for preparing the next coating.

[0032] 5. Application of the above-mentioned coating materials and preparation methods thereof, as well as anti-fog and anti-fouling coatings and preparation methods thereof

[0033] The above-mentioned coating material, the preparation method of the coating material, the anti-fog and anti-fouling coating, and the preparation method of the anti-fog and anti-fouling coating can all be used for the preparation of medical transparent materials, especially the preparation of medical endoscopes.

[0034] The beneficial effects of the present invention are:

[0035] 1. The PDMS mold with a surface microstructure array prepared by the present invention can be reused, and the preparation does not require photolithography technology and the preparation conditions are simple.

[0036] 2. The monomers used in the ternary copolymer coating material prepared by the present invention are all commonly available, low-cost monomers with good biocompatibility, making them suitable for applications in the field of medical materials. Furthermore, the BP group employed in the present invention acts as both a crosslinker within the polymer and an anchor group for interfacial adhesion, providing strong adhesion to the substrate and effectively preventing excessive moisture absorption, swelling, wrinkling, and shedding of the coating, thereby improving the anti-fog stability and durability of the coating.

[0037] 3. The anti-fog coating prepared by the present invention has the characteristics of simple preparation process conditions, high transparency, strong adhesion, good anti-fog and anti-fouling properties, good biocompatibility, and suitability for mass production. It can also ensure light transmittance while having excellent anti-fog and anti-fouling effects, and can be widely used in medical transparent materials, especially in the anti-fog and anti-fouling of medical endoscopes. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is the particle size distribution diagram of SiO2 balls prepared in Example 1; Figure 1 (a) is the particle size distribution diagram of SiO2 spheres with a particle size of 350 nm; Figure 1 (b) is the particle size distribution diagram of SiO2 spheres with a particle size of 650 nm;

[0039] Figure 2 The following is a flow chart of the preparation of the PDMS mold in Example 1 and the corresponding SEM image; Figure 2 (a) Preparation process of PDMS mold; Figure 2 (b) Preparation of PDMS mold based on SiO2 spheres with a particle size of 350 nm; Figure 2 (c) Preparation of PDMS mold based on SiO2 spheres with a particle size of 650 nm;

[0040] Figure 3 The SEM and AFM images of the anti-fog and anti-fouling coating NA-CS having a surface microstructure array in Example 1 are shown; Figure 3 (a) is the SEM image; Figure 3 (b) AFM image;

[0041] Figure 4 This is the SEM image of the PDMS mold after repeated use in Example 1;

[0042] Figure 5 The coating materials PSTB5, PSTB8, and PSTB prepared in Examples 1 to 3 10 of 1 H-NMR spectrum;

[0043] Figure 6 The photoreaction mechanism diagram of the coating material PSTB as a function of UV irradiation time and the UV absorption spectrum of the polymer PSTB5 prepared in Example 1 are shown; Figure 6 (a) is the photoreaction mechanism diagram; Figure 6 (b) is the UV absorption spectrum;

[0044] Figure 7 The coatings CS5, CS8 and CS prepared in Examples 1 to 3 10 ATR-FTIR and XPS spectra; Figure 7 (a) is the ATR-FTIR graph; Figure 7 (b) is the XPS spectrum;

[0045] Figure 8 The results of the cross-hatch test and the shear force test are shown in Figure 2. Figure 8 (a) Cross-hatch test results of CS5 and CS5 / d prepared in Example 1; Figure 8 (b) is a schematic diagram of the coating shear force test; Figure 8 (c) Shear force curves of CS5 and CS5 / d; Figure 8 (d) is the coating CS 5、 CS5 / d, CS 8、 CS8 / d 、 CS 10 and CS 10 / d adhesion strength;

[0046] Figure 9 The transmittance test results of the coatings (CS and NA-CS) prepared in Examples 1 to 3 and the bare substrate (comparative example) are shown; Figure 9 (a) is the transmittance curve in the visible light range; Figure 9 (b) is the transmittance curve under the anti-fog test; Figure 9 (c) is a photo of the anti-fog effect under the anti-fog test;

[0047] Figure 10 The anti-protein adhesion test results of the coatings (CS and NA-CS) prepared in Examples 1 to 3 and the bare substrate (comparative example); Figure 10(a) Fluorescence microscopic imaging of FITC-BSA residual on the coating surface; Figure 10 (b) is the fluorescence intensity standard curve of FITC-BSA; Figure 10 (c) Fluorescence intensity analysis of residual FITC-BSA on the coating surface.

[0048] Figure 11 The antibacterial adhesion test results of the coatings (CS and NA-CS) prepared in Examples 1 to 3 and the bare substrate are shown; Figure 11 (a) is a schematic diagram of the actual object; Figure 11 (b) Schematic diagram of bacterial numbers. DETAILED DESCRIPTION

[0049] The present invention is described in more detail below with reference to the accompanying drawings and examples. However, the present invention is not limited thereto. A person skilled in the art may make various improvements and modifications without departing from the technical principles of the present invention, and such improvements and modifications are considered to be within the scope of protection of the present invention. Any matters not described in detail in this specification constitute prior art known to those skilled in the art.

[0050] The present invention aims to construct a polymer coating with a surface microstructure array. First, a PDMS mold with a surface microstructure array is prepared using the LB method and the thermoplasticity of PDMS. Sulfobetaine methacrylate (SBMA) with good anti-protein adhesion and biocompatibility is selected as the hydrophilic monomer, trifluoroethyl methacrylate (TFEMA) as the hydrophobic monomer, and 4-acryloyloxybenzophenone (BPA) as the anchor monomer. AIBN-initiated free radical polymerization is used to synthesize the terpolymer poly(SBMA- co -TFEMA- co The PSTB solution was then cured using a mold method and UV light to produce an anti-fog and anti-fouling coating with a surface microstructure array. This coating exhibits high transparency, strong adhesion, and excellent anti-fog and anti-fouling properties. It also exhibits good biocompatibility and has shown promising application in medical endoscopes.

[0051] The preparation process of the present invention is specifically as follows:

[0052] S1) Preparation of a polydimethylsiloxane (PDMS) mold with a surface microstructure array:

[0053] S1.1) A densely packed and uniform monolayer of silica was prepared on the glass surface by self-assembly using a dispersion of 0.5–5 wt % silica spheres in n-butanol using the Langmuir-Blodgett (LB) method.

[0054] The silica spheres have a particle size of nanometer scale and can be prepared using tetraethyl orthosilicate as a silicon source.

[0055] Nano-sized silica spheres of different particle sizes can be obtained by adjusting the ratio of ammonia water according to the following raw materials in parts by volume: 1-5 parts of tetraethyl orthosilicate, 20-50 parts of anhydrous ethanol, 1-10 parts of ammonia water and 5-10 parts of deionized water.

[0056] The specific process for preparing silica spheres is as follows: Tetraethyl orthosilicate and anhydrous ethanol are uniformly mixed to obtain Liquid A, where the mass fraction of tetraethyl orthosilicate in Liquid A is 20-50%. Ammonia water, anhydrous ethanol, and deionized water are uniformly mixed to obtain Liquid B, where the mass fraction of Liquid B is 1-3%. Liquid A is added to Liquid B and reacted at room temperature to obtain a milky white suspension. The suspension is centrifuged, and the precipitate is collected and dispersed with an appropriate amount of ethanol. This centrifugal dispersion process is repeated 3-5 times to remove the ammonia water and unreacted tetraethyl orthosilicate. The precipitate is dried to obtain silica spheres.

[0057] Among them, the preparation process of single-layer silica is specifically as follows: a dispersion of silica balls with a mass fraction of 0.5~5wt% in n-butanol is used to draw a film upward in a direction perpendicular to the water surface using the LB method. During the film drawing process, the moving speed of the glass sheet is 2~10 mm / min. After drawing the film, a single-layer silica is obtained that is tightly and evenly arranged on the glass surface.

[0058] In the present invention, by adjusting the particle size of nano-scale silica spheres, the size of the microstructure array on the surface of the PDMS mold can be controlled. By using PDMS molds with surface microstructure arrays of various sizes, coatings with surface microstructure arrays of various sizes can be prepared on the surface of the substrate.

[0059] S1.2) Transfer the silica monolayer from the glass surface to the PDMS surface using polydimethylsiloxane (PDMS). Specifically, inject a mixture of PDMS and a crosslinker (preferably a 10:1 ratio of PDMS mass to crosslinker mass) onto the glass surface. Heat cure at 30-60°C for 1-5 hours, then peel off the PDMS film. The molecular weight of PDMS is preferably 600-1000.

[0060] S1.3) Finally, use a 0.5-5% volume fraction hydrofluoric acid (HF) solution to wash away the silica partially embedded in the PDMS membrane surface. After soaking for 1-10 minutes, a PDMS mold with a surface microstructure array is obtained.

[0061] S2) Synthesis of a terpolymer poly(SBMA-co-TFEMA-co-BPA) (PSTB) with anti-fog and anti-fouling effects: 1-20 parts of sulfobetaine methacrylate (SBMA), 0.01-2 parts of trifluoroethyl methacrylate (TFEMA), and 0.05-0.2 parts of 4-acryloxybenzophenone (BPA) were dissolved in trifluoroethanol, based on the molar ratio. The mixture was uniformly mixed to obtain a colorless, transparent solution with a total mass concentration of 5-20 wt%. In an inert atmosphere, 0.05-0.1 parts of azobisisobutyronitrile (AIBN) as a polymerization initiator was added, and the crude terpolymer was synthesized by a free radical polymerization reaction initiated by AIBN at 50-70 °C.

[0062] Post-treatment: The crude product suspension of the terpolymer was centrifuged, and the supernatant was removed and the resulting white precipitate was redispersed in trifluoroethanol. The above centrifugation-dispersion operation was repeated three times. Finally, the resulting precipitate was dried in a vacuum oven at 45 °C for 24 h to obtain the terpolymer.

[0063] The inert atmosphere is any one of nitrogen, helium, neon, argon, krypton and radon, or a combination of two or more.

[0064] The reaction formula of the above-mentioned free radical polymerization reaction is specifically:

[0065]

[0066] Among them, x:y:z=1~20:0.01~2:0.05~0.2.

[0067] Preferably, the relative molecular weight of the terpolymer PSTB obtained in this step is 4000-8000.

[0068] S3) Preparing a polymer coating having a surface microstructure array: injecting a 10-20 wt% terpolymer solution (solvent: trifluoroethanol) into one side of a PDMS mold having a surface microstructure array and covering the surface with a substrate, so that the side of the PDMS mold having the surface microstructure array is in contact with the surface of the substrate to be coated. After UV curing for 5-40 minutes, the PDMS mold is peeled off to obtain an anti-fog and anti-fouling coating having a surface microstructure array.

[0069] Among them, the polymer-based transparent substrate specifically refers to a polymer-based transparent substrate containing a hydrocarbon chain (such as polyethylene terephthalate PET, polymethyl methacrylate PMMA, polyethylene PE, etc.).

[0070] In step S3), the benzophenone groups (hereafter referred to as BP groups) in the coating material's terpolymer undergo a step transition under UV light, covalently bonding to the hydrocarbon chains on the surface of the polymer-based transparent substrate. This creates a crosslinked network within the linear polymers and a covalent bond at the interface between the coating and the substrate, enhancing coating stability and adhesion.

[0071] S4) After rinsing the PDMS mold peeled from the substrate with anhydrous ethanol, the rinsed PDMS mold is recovered. The recovered PDMS mold can be used for the preparation of the next coating and reused multiple times. The preparation process of the next coating is the same as step S3).

[0072] The above-mentioned anti-fog and anti-fouling coating material and preparation method thereof, anti-fog and anti-fouling coating and preparation method thereof can be used for the preparation of medical transparent materials, especially for the preparation of medical endoscopes.

[0073] The specific embodiments of the present invention are as follows: Example

[0074] S1) Preparation of a polydimethylsiloxane (PDMS) mold with a surface microstructure array.

[0075] S1.1) Preparation of silica spheres: Mix 12.4 mL of tetraethyl orthosilicate (TES) and 32 mL of anhydrous ethanol (Solution A). Mix 20 mL of 25 wt% aqueous ammonia, 20 mL of anhydrous ethanol, and 320 mL of deionized water (Solution B). Quickly add Solution A to Solution B and allow to react at room temperature for 10 hours. The colorless, transparent solution will turn into a milky white suspension. After the reaction, centrifuge the suspension at 2000 rpm for 10 minutes. Remove the supernatant to obtain a white solid. Disperse the solid with an appropriate amount of ethanol and centrifuge again. Repeat this centrifugal dispersion process 3–5 times to remove the ammonia and unreacted TES. Then, dry the solid in a 45°C oven for 6 hours to obtain SiO2 particles with a size of 350 nm. Changing the amount of aqueous ammonia to 30 mL, while keeping all other conditions unchanged, yields SiO2 particles with a size of 650 nm.

[0076] S1.2) PDMS mold preparation: Disperse SiO2 in n-butanol to obtain a 2 wt% SiO2 n-butanol dispersion. Using the Langmuir-Blodgett method, deposit a uniformly aligned SiO2 monolayer onto the glass surface using this n-butanol dispersion at a speed of 2–10 mm / min.

[0077] Transferring SiO2 from the glass surface using PDMS: PDMS was injected onto the glass surface (PDMS: cross-linker ratio: 10:1), heat-cured in a 50°C oven for 3 hours, and then the PDMS membrane was peeled off. The PDMS membrane was then soaked in a 2 wt% HF solution for 5 minutes to wash away the semi-embedded SiO2 on the PDMS membrane, resulting in a PDMS mold.

[0078] In this example, two SiO2 particles with different sizes were used to prepare PDMS molds with different surface microstructure arrays. 350 , NA 650 .

[0079] S2) synthesizing a terpolymer with anti-fog and anti-fouling effects.

[0080] Synthesis of Polymer PSTB5: SBMA (5.5921 g), TFEMA (0.6721 g), and BPA (0.0606 g) were added to a round-bottom flask and dissolved in 73 mL of trifluoroethanol. The initiator AIBN (0.0398 g) was then added, and deoxygenation was performed with argon for 30 minutes. The reaction was allowed to proceed at 70°C for 10 hours, yielding a white suspension. The suspension was then centrifuged, the supernatant removed, and the white precipitate redispersed in trifluoroethanol. This centrifugation-dispersion process was repeated three times. Finally, the resulting precipitate was dried in a vacuum oven at 45°C for 24 hours to yield polymer PSTB5.

[0081] S3) Prepare a conventional coating CS and a polymer coating NA-CS with a surface microstructure array, respectively.

[0082] Preparation of the CS5 coating: PSTB5 was dissolved in trifluoroethanol to obtain a 10 wt% PSTB5 solution. The solution was then spin-coated onto a PET plate and cured with UV light for 30 minutes to obtain CS5.

[0083] Preparation of anti-fog and anti-fouling coating NA-CS5 with surface microstructure array: PSTB5 was dissolved in trifluoroethanol to obtain a 20 wt% PSTB5 solution. The solution was drop-coated on a PDMS mold using a micro-transfer molding method and the substrate was covered on top. After UV curing for 30 minutes, the mold was peeled off from the substrate surface to obtain NA-CS5. This example uses two PDMS molds with different surface microstructure arrays. According to this process, two anti-fog and anti-fouling coatings with surface microstructure arrays were prepared, namely NA 350 -CS5, NA 650 -CS5. Example

[0084] Synthesis of Polymer PSTB8: SBMA (4.4710 g), TFEMA (0.3362 g), and BPA (0.0454 g) were added to a round-bottom flask and dissolved in 56 mL of trifluoroethanol. The initiator AIBN (0.0298 g) was then added, and deoxygenation was performed with argon for 30 minutes. The reaction was allowed to proceed at 70°C for 10 hours, yielding a white suspension. The suspension was then centrifuged, the supernatant removed, and the white precipitate redispersed in trifluoroethanol. This centrifugation-dispersion process was repeated three times. Finally, the resulting precipitate was dried in a vacuum oven at 45°C for 24 hours to yield polymer PSTB8.

[0085] Coating CS8, NA 350 -CS8 and NA 650 -The preparation process of CS8 is the same as that of Example 1. Example

[0086] Polymer PSTB 10 Synthesis: SBMA (5.5861 g), TFEMA (0.3365 g), and BPA (0.0555 g) were added to a round-bottom flask and dissolved in 56 mL of trifluoroethanol. The initiator AIBN (0.0364 g) was then added and deoxygenated with argon for 30 minutes. The reaction was carried out at 70 °C for 10 hours to obtain a white suspension. The suspension was then centrifuged, the supernatant removed, and the white precipitate redispersed in trifluoroethanol. This centrifugation-dispersion process was repeated three times. Finally, the resulting precipitate was dried in a vacuum oven at 45 °C for 24 hours to obtain the polymer PSTB. 10 .

[0087] Coating CS 10 , NA 350 -CS 10 and NA 650 -CS 10 The preparation process is the same as in Example 1.

[0088] Furthermore, when the BP groups in the polymer coating are excited by UV light, they undergo a transition from an np* state to a triplet state, abstracting hydrogen atoms from the aliphatic hydrocarbon-containing substrate. This allows the BP groups to covalently bond to the polyethylene terephthalate (PET). The polymer provides multiple reactive sites for cross-linking with the substrate. Therefore, the BP groups, acting as anchoring groups, play a key role in forming a stable coating on the substrate surface.

[0089] Comparative Example

[0090] This comparative example is a bare substrate without coating.

[0091] The test results of the coatings prepared in Examples 1 to 3 and the coatings having surface microstructure arrays and the comparative examples are as follows:

[0092] Figure 1 is the particle size distribution diagram of SiO2. Figure 1 As shown in the figure, the SiO2 prepared has a uniform particle size distribution, and the particle sizes are 350 nm ( Figure 1 (a)) and 650 nm( Figure 1 (b)).

[0093] like Figure 2 As shown in the figure, the preparation of PDMS mold is divided into three steps: Figure 2 (a)) and the corresponding morphology ( Figure 2 (b) Figure 2 (c) Characterization. First, a densely packed single layer of SiO2 was self-assembled on a glass slide using the LB method. The rapid prototyping properties of PDMS were then utilized to transfer the SiO2 layer from the glass surface to the PDMS surface. Finally, the SiO2 on the PDMS surface was washed away with an HF solution to obtain a PDMS mold.

[0094] Figure 3 The SEM and AFM images of NA-CS. 350 -CS and NA 650 The surfaces of the NA-CS films exhibited regularly arranged nanoscale emulsified protrusions with diameters of 350 nm and 650 nm, respectively, and protrusion heights of 100 nm and 200 nm, respectively. These results demonstrate that the polymer solution was successfully coated on the substrate surface and that NA-CS films were successfully prepared.

[0095] like Figure 4 As shown in the figure, the two PDMS molds were rinsed with ethanol and dried after peeling, and the surface morphology did not change significantly, so they could be reused.

[0096] like Figure 5 For polymer PSTB 1 H-NMR spectrum. The peaks at 0.78~2.04 ppm correspond to the hydrogen on the polymer main chain, and the peak at 3.15 ppm corresponds to the hydrogen on the dimethyl group connected to the quaternary ammonium on the sulfonate betaine side chain (-N + The peak at 3.96 ppm corresponds to the hydrogen on the methylene group attached to the trifluoromethyl group (-CH2-CF3), and the peaks at 7.19–7.86 ppm correspond to the hydrogen on the benzene ring of the side chain benzophenone group (-Ph-H). These analyses confirmed the successful synthesis of PSTB.

[0097] Figure 6The following is a diagram of the photoreaction mechanism of polymer PSTB and its UV absorption spectrum under UV irradiation. Upon UV irradiation, the BP group on the PATB side chain transforms into a triplet excited state through internal electronic transition. In this state, the BP group can capture a proton on the adjacent carbon chain, and the two newly generated carbon radicals subsequently form a new CC covalent bond. Figure 6 As shown in (b), the absorbance of the BP group at 257 nm decreases with increasing UV irradiation time. The characteristic peak of the BP group disappears after 30 minutes of UV irradiation, confirming the UV reaction of the BP group.

[0098] Figure 7 The ATR-FTIR and XPS images of CS are shown in Figure 2. Since CS and NA-CS use the same polymer, only CS was selected for testing. Figure 7 As shown in (a), CS at 3480 cm -1 The absorption peak at 1037~1172 cm is derived from the stretching vibration of the carboxyl group. -1 The peak band at -SO3 - , at 660 cm -1 The peak at comes from the stretching vibration of -CF3. Figure 7 As shown in (b), the XPS spectrum of the bare substrate shows only C element peaks and O element peaks, with the peak positions of C1s (289.9 eV) and O1s (532.5 eV) respectively; while CS5, CS8 and CS 10 The spectrum shows peaks for the elements C, O, F, and N, with the peak positions being C1s (289.9 eV), O1s (532.5 eV), F1s (688.3 eV), and N1s (403.7 eV), respectively. Furthermore, S peaks (231.6 eV and 167.6 eV) were observed in the high-resolution S spectrum. Therefore, the XPS spectrum of CS exhibits peaks for the elements C, O, F, N, and S. These results further demonstrate the successful coating of the substrate surface.

[0099] Figure 8 The following are the test results of the adhesion between the coating and the substrate. The cross-cut tape peeling test and the shear force test were used to qualitatively and quantitatively measure the adhesion of the coating after UV curing. Figure 8 As shown in (a), after the tape is peeled off, the coating treated with UV irradiation does not fall off, while the coating without UV treatment has obvious coating falling off at the edge of the scratch. Figure 8 As shown in (b), after UV treatment, the adhesion strength of the coating with a BP-based interfacial layer is about 2.5 times that of the control. The above results indicate that the adhesion of the coating with a BP-based interfacial layer is significantly enhanced.

[0100] Figure 9The transmittance of the sample in the visible light wavelength range was quantitatively evaluated by UV-visible spectroscopy. Figure 9 As shown in (a), the effect of the coating on the optical properties of the substrate itself can be ignored (the average transmittance curves of each sample are similar, >90%). Figure 9 (b) and Figure 9 (c) shows the anti-fog test results for the coatings prepared in Examples 1-3. Compared to the bare substrate, the coated substrates exhibited significant anti-fog effects. In the thermal anti-fog test (80°C, 100% relative humidity), the entire bare substrate was immediately covered by condensation droplets, resulting in low transmittance (<40%). However, the CS and NA-CS coatings maintained high average transmittances.

[0101] Figure 10 and Figure 11 The results of the protein and bacteria resistance tests of the coatings prepared in the examples are shown in the figure. As shown in the figure, compared with the bare substrate, the CS and NA-CS surfaces have obvious anti-protein and anti-bacterial effects, and the NA-CS has better anti-fouling effect.

[0102] Combined with the above test results, it can be seen that the anti-fog and anti-fouling coating prepared by the present invention has a simple preparation method, firmly adheres to the substrate, and can achieve excellent anti-fog and anti-fouling effects while ensuring light transmittance.

[0103] The above description is only a preferred specific embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention within the technical scope disclosed in the present invention, and these changes should be covered by the scope of protection of the present invention.

Claims

1. A method for preparing an anti-fog and anti-fouling coating having a surface microstructure array, characterized in that: The preparation method specifically comprises the following steps: S1) preparing a PDMS mold having a surface microstructure array: forming a monolayer of silica on a glass surface using a silica sphere solution, then transferring the monolayer of silica from the glass surface to a PDMS membrane surface using PDMS, and finally washing the PDMS membrane with a hydrofluoric acid solution to obtain a PDMS mold having a surface microstructure array; wherein the silica spheres in the silica sphere solution have a particle size of nanometers; S2) preparing a polymer coating having a surface microstructure array: injecting a coating material solution into a PDMS mold and covering it with a substrate, and peeling off the PDMS mold after UV curing to obtain an anti-fog and anti-fouling coating having a surface microstructure array; the solvent of the coating material solution is trifluoroethanol, and the mass concentration is 10-20wt%; The coating material is prepared by using the following raw materials in parts by weight: 1-20 parts of sulfobetaine methacrylate, 0.01-2 parts of trifluoroethyl methacrylate, 0.05-0.2 parts of 4-acryloyloxybenzophenone and 0.05-0.1 parts of azobisisobutyronitrile; The preparation method of the coating material is specifically as follows: sulfobetaine methacrylate, trifluoroethyl methacrylate and 4-acryloyloxybenzophenone are co-dissolved in trifluoroethanol to obtain a reaction stock solution, wherein the mass concentration of the reaction stock solution is 5-20wt%; then, azobisisobutyronitrile is added to the reaction stock solution, and the reaction is carried out at 50-70°C under an inert gas atmosphere. After the reaction is completed, the coating material is obtained.

2. The method for preparing an anti-fog and anti-fouling coating having a surface microstructure array according to claim 1, wherein: In step S1), the process of forming a monolayer of silica on the surface of the glass sheet using the silica ball solution is specifically as follows: according to the Langmuir-Blodgett method, a film is drawn using the silica ball solution at a drawing speed of 2-10 mm / min; the solvent of the silica ball solution is n-butanol, and the mass concentration is 0.5-5 wt%.

3. The method for preparing an anti-fog and anti-fouling coating having a surface microstructure array according to claim 1, wherein: In step S1), the process of transferring the single layer of silicon dioxide from the glass surface to the surface of the PDMS film using PDMS is specifically as follows: PDMS is mixed with a curing agent, poured onto the single layer of silicon dioxide on the surface of the glass sheet, and cured at 30-60 ° C for 1-5 hours before peeling off the PDMS film.

4. The method for preparing an anti-fog and anti-fouling coating having a surface microstructure array according to claim 1, wherein: In step S1), the process of washing away the single layer of silicon dioxide on the surface of the PDMS membrane with a hydrofluoric acid solution is specifically as follows: the PDMS membrane with the single layer of silicon dioxide embedded on the surface is immersed in a hydrofluoric acid solution with a volume fraction of 0.5-5% for 1-10 minutes.

5. The method for preparing an anti-fog and anti-fouling coating having a surface microstructure array according to claim 1, wherein: In the step S2), the substrate is a polymer-based transparent substrate.

6. An anti-fog and anti-fouling coating having a surface microstructure array, characterized in that: The anti-fog and anti-fouling coating is obtained by the preparation method according to any one of claims 1 to 5.

7. An application of an anti-fog and anti-fouling coating obtained by the preparation method according to any one of claims 1 to 5, characterized in that: Used for the preparation of medical transparent materials.

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