Self-cleaning, waterproof and heat-dissipating coating, and preparation method and application thereof

Abstract

The application discloses a self-cleaning, waterproof and heat-dissipating coating as well as a preparation method and application thereof. The preparation method of the self-cleaning, waterproof and heat-dissipating coating comprises the following steps: uniformly mixing perfluoro 1,2-dimethylcyclohexane and hexafluoropropylene dimer at 20-35 DEG C; after the reaction is completed, adding perfluorodecyl acrylate into the mixture, and stirring at 20-35 DEG C for a set time; after the stirring is completed, adding AIBN into the reaction system, heating, allowing the perfluorodecyl acrylate to self-crosslink and polymerize for a set time, and thus the coating is obtained. Compared with a traditional sliding coating, the SUSC effectively solves the problem of the self-cleaning performance decline caused by the lubricant loss. The SUSC coating also has a low sliding angle (about 8 DEG ), high transparency and good heat-dissipating property.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to a self-cleaning, waterproof, and heat-dissipating coating, its preparation method, and its application. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] With the rapid development of high-performance electronic components, the power density of electronic devices has increased dramatically. Poor waterproofing, cleaning, and heat dissipation performance of electronic components often leads to malfunctions. Functional coatings for high-power-density electronic components are crucial for the development of next-generation integrated electronic devices. Traditional encapsulation coatings, such as waterproof films and heat sinks, have already played an important role in the operation of electronic systems. Currently, transparent electronic products, including displays, solar cells, smart windows, and wearable medical heating patches such as electronic skin, are widely used in modern society. However, their application also faces many challenges. For example, high optical transparency and a clean surface are essential for solar cells. Dust accumulation on the surface often leads to low photovoltaic (PV) conversion efficiency or even hot spots, which can cause irreversible damage to the solar panel. For more complex circuit boards, waterproofing and heat dissipation performance are critical. To improve the operating efficiency of electronic devices under different operating conditions, it is necessary to prepare a coating material with good ultra-slippery self-cleaning properties, high light transmittance, and heat dissipation.

[0004] Lotus-shaped superhydrophobic surfaces with micro / nano-rough structures and low surface energy have attracted widespread attention due to their self-cleaning properties. However, their low transparency and rough structure hinder their application in the electronics field. Aizenberg et al. prepared a liquid-injected porous slip surface (SLIPS) with a large amount of flowing lubricant on its surface and no trapped air. This smooth surface was fabricated by injecting lubricant into a rough porous micro / nanostructure substrate (such as metal, glass, plastic, ceramic, wood, fabric, elastomer, etc.). Other methods involve perfuming perfluoroalkyl ethers onto micro / nanoporous substrates, which can repel almost all immiscible materials. However, low surface energy perfluoropolyethers or other perfluorinated liquids as lubricants are expensive, toxic, and environmentally harmful. Furthermore, a method using femtosecond laser direct writing to prepare porous network microstructures followed by silicone oil injection has been developed to obtain a smooth surface. However, the loss of flowing lubricant on the smooth surface leads to a decrease in sliding ability.

[0005] To avoid using flowing lubricants, smooth, low-surface-energy paraffin or polymer layers are used instead of smooth surfaces. While lubricant-free smooth surfaces have attracted considerable attention, their poor smoothness, low optical transparency, high thickness, high curing temperature, and poor heat dissipation limit their practical application in electronic devices. Therefore, a new coating material is needed to promote the practical application of smooth surfaces in various electronic devices. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a self-cleaning, waterproof, and heat-dissipating coating, its preparation method, and its application.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] In a first aspect, the present invention provides a method for preparing a self-cleaning, waterproof, and heat-dissipating coating, comprising the following steps:

[0009] Mix perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer at 20-35°C;

[0010] After the reaction is complete, perfluorodecyl acrylate and isobornyl acrylate are added to the mixture, and the mixture is stirred at 20-35°C for a set time.

[0011] After stirring, AIBN is added to the reaction system and heated to allow perfluorodecyl acrylate and isobornyl acrylate to crosslink and polymerize for a set time, thus obtaining the coating.

[0012] The reaction of perfluorodecyl acrylate is as follows:

[0013]

[0014] The inventors discovered in their experiments that solvents used as isobornyl acrylate (such as ethyl acetate and ethanol) generally have high boiling points, above 60°C. After the polymerization of perfluorodecyl acrylate and isobornyl acrylate is complete, the resulting coating is difficult to cure at room temperature and typically requires heating in an oven. However, the coating in this invention is intended for spraying onto the surface of electronic components. Electronic components are highly precise and have stringent environmental requirements; excessively high drying temperatures can damage the precision of electronic components and even affect their lifespan.

[0015] After repeated screening of solvents, it was found that when perfluoro-1,2-dimethylcyclohexane and hexafluoropropylene dimer are used as solvents, perfluorodecyl acrylate and isobornyl acrylate can be effectively dissolved. After the perfluorodecyl acrylate and isobornyl acrylate have completed cross-linking polymerization, the coating can be applied to the substrate and cured rapidly at room temperature within 60-80 seconds, thus meeting the application requirements of electronic component coatings.

[0016] Furthermore, when perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer are used as solvents, the coating is applied to the substrate surface. During the curing process, the perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer do not volatilize but are cured as the base material of the coating. Together with the crosslinking polymerization products of perfluorodecyl acrylate and isobornyl acrylate, they form a coating and work together to give the coating good waterproof, heat dissipation and self-cleaning properties.

[0017] In some embodiments, the mass ratio of perfluoro1,2-dimethylcyclohexane, hexafluoropropylene dimer, perfluorodecyl acrylate, and isobornyl acrylate is 10-15:4-6:0.01-0.05:0.01-0.05.

[0018] Preferably, the mass ratio of perfluoro1,2-dimethylcyclohexane, hexafluoropropylene dimer, and perfluorodecyl acrylate is 10-13:4-10:0.02-0.04:0.02-0.04.

[0019] Preferably, the mass ratio of perfluorodecyl acrylate to AIBN is 2-4:1.

[0020] In some embodiments, the perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer are stirred at 20-35°C for 20-40 minutes.

[0021] In some embodiments, after adding perfluorodecyl acrylate and isobornyl acrylate to the mixture, the stirring time is 10-30 min.

[0022] In some embodiments, the crosslinking polymerization of perfluorodecyl acrylate and isobornyl acrylate is carried out at a temperature of 55-65°C for 1.5-2.5 hours.

[0023] Secondly, the present invention provides a self-cleaning, waterproof, and heat-dissipating coating, which is prepared by the aforementioned preparation method.

[0024] Thirdly, the present invention provides the application of the self-cleaning, waterproof, and heat-dissipating coating in the coating and encapsulation of electronic devices.

[0025] In some embodiments, when coating and encapsulating electronic devices, the coating is dropped or applied to the surface of the electronic device and cured at 20-35°C.

[0026] The beneficial effects achieved by one or more embodiments of the present invention described above are as follows:

[0027] This invention presents a SUSC material for electronic device coatings, exhibiting excellent waterproofing, heat dissipation, and self-cleaning properties, prepared through the polymerization of perfluorododecyl acrylate monomers. Results show that this multifunctional coating is suitable for various applications. Compared to traditional sliding coatings, SUSC effectively solves the problem of decreased self-cleaning performance due to lubricant loss. The SUSC coating also features a low slip angle (≈8°), high transparency, and good heat dissipation (high transparency is due to the transparency of all selected raw materials and the minimal generation of hydrogen bonds during crosslinking; the low slip angle is due to the low surface energy of the fluorinated chains and the upward alignment of the flexible chains to form a brush-like structure; and the heat dissipation is due to its ultra-thin thickness (approximately 1.5 μm) and relatively low polymer crosslinking density). The superior properties of the SUSC coating make it an excellent anti-slip material, widely applicable in fields such as solar power generation and chip waterproofing. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 In the figures, a) is a SEM image of the SUSC coating; b) is an energy dispersive spectroscopy (EDS) spectrum of fluorine in the SUSC; c) is a cross-sectional SEM image of the coated SUSC; d) and e) are AFM images of the SUSC coating on a glass substrate; f) are FTIR spectra of PFDA and uncured SUSC; g) is an XPS spectrum of the coated SUSC. Insets: Schematic diagram of the highly ordered crystallization of perfluoroalkyl side groups; h) is the elemental C spectrum of the coated SUSC XPS; i) is the elemental O peak diagram of the coated SUSC XPS.

[0030] Figure 2 In the images, a) shows the UV-VIS-NIR transmission spectra and transparent images of uncoated and SUSC coated glass; b) shows images of water (30 μL) and n-dodecane (30 μL) droplets with sliding markings on SUSC; c) shows an image of water droplets (30 μL) with sliding markings on PDMS; and d) shows an image of water droplets (30 μL) with sliding markings on PVDF.

[0031] Figure 3In the diagram, a) is a high-speed camera image of water droplets on the SUSC surface; b) is the surface free energy of uncoated glass, PDMS, and SUSC; c) is the sliding angle and contact angle hysteresis of the uncoated glass, PDMS, and SUSC surfaces; d) is a schematic diagram of droplet sliding on the uncoated glass, PDMS, and SUSC surfaces; e)-g) are characterization diagrams of the effect of hot steam on the formation of droplet aggregates on the uncoated copper sheet; h)-j) are characterization diagrams of high-temperature steam and condensed water droplets on the SUSC-coated copper plate.

[0032] Figure 4 In the image, a) is a schematic diagram of contaminants of different sizes from nanometers to centimeters; b) and f) are SEM images of TiO2 nanoparticle (≈20nm) residues on uncoated glass and SUSC; c) and g) are SEM images of TiO2 nanoparticle residues on uncoated glass and SUSC; d) and h) are SEM images of SiO2 nanoparticle (≈1μm) residues on uncoated glass and SUSC; e) and i) are a comparison of contamination between uncoated glass and SUSC containing gravel (≈200μm) before and after rinsing with water droplets (tilt angle ≈10°).

[0033] Figure 5 In the image, a) shows infrared thermal images of PU and SUSC from approximately 60°C to 50°C and a comparison of cooling times; b) shows the cooling of PU and SUSC at room temperature; c) shows the temperature changes of PU and SUSC during cyclic testing (heated to the same temperature and then cooled at room temperature).

[0034] Figure 6 In the diagram, a) shows the working principle of a SUSC-coated LED lamp in NaCl solution; b) shows the working state of LED bulbs without coating and coated with SUSC in NaCl solution; c) shows the working state of a circuit board after being coated with SUSC in NaCl solution; and d) shows a SEM cross-sectional view of the SUSC-coated copper wire.

[0035] Figure 7 Comparative images show the curing of the coatings prepared in Example 2, Comparative Example 1, and Comparative Example 2 of this invention on metal substrates at room temperature. Detailed Implementation

[0036] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] The present invention will be further described below with reference to the embodiments.

[0038] Material

[0039] Perfluorodecyl acrylate (PFDA) and isobornyl acrylate (IBOA) were purchased from Maclean Biotech Inc. (Shanghai).

[0040] Azobisisobutyronitrile (AIBN) was supplied by Aladdin Biochemical Technology Co., Ltd. (Shanghai).

[0041] Anhydrous ethanol was purchased from Sinopharm Chemical Reagent Co., Ltd., and polydimethylsiloxane (PDMS) was purchased from Shenzhen Hongyejie Technology Co., Ltd.

[0042] The perfluoro-1,2-dimethylcyclohexane and hexafluoropropylene dimer were supplied by Guochen Taifu Co., Ltd. (Jinan).

[0043] The PU was purchased from China Daoguan Co., Ltd.

[0044] Polyvinylidene fluoride (PVDF) was supplied by Zhongcheng Plastics Co., Ltd. (Jieyang, China).

[0045] All chemicals are analytical grade and can be used without further purification.

[0046] Example 1

[0047] Preparation of solid smooth coating

[0048] 7 mL of perfluoro-1,2-dimethylcyclohexane and 3 mL of hexafluoropropylene dimer were added to a 100 mL round-bottom flask and magnetically stirred. After stirring at room temperature for 30 minutes, 0.03 g of perfluorodecyl acrylate and 0.02 g of isobornyl acrylate were added to the mixture. The mixture was stirred at room temperature for 15 minutes. 0.01 g of azobisisobutyronitrile (AIBN) was added dropwise to the mixture, allowing the perfluorodecyl acrylate to crosslink and polymerize with the isobornyl acrylate at 60 °C for 2 h. After the reaction, the resulting suspension was spin-coated onto a substrate and then rapidly cured at room temperature (25 °C) to form an ultra-smooth, pure solid surface.

[0049] Surface morphology of SUSC coating

[0050] The morphology of the SUSC coating surface was observed using scanning electron microscopy (SEM). Elemental distribution was scanned using a field emission scanning electron microscope (SUPRA™, 55 Zeiss, Germany). After SUSC was sprayed onto a glass substrate and cured, it was quenched with liquid nitrogen. Each sample was cleaned with nitrogen before testing, and then gold was sprayed onto the sample surface. The testing temperature was 25°C, and AFM measurements were performed using a Dimension atomic force microscope (ICON2-SYS, Bruker, USA).

[0051] Structural characterization of SUSC

[0052] The prepared SUSC emulsion was characterized by FTIR and XPS. Fourier transform infrared (FTIR) spectra were acquired on a spectrometer (Nicolet IS20, Thermo Fisher Scientific Inc., Waltham, MA, USA), with a scanning range of 4000–400 cm⁻¹. –1 The scanning speed was 2 mm / s. X-ray photoelectron spectroscopy (XPS) was performed on a monochromatic al-k-α source k-α photoelectron spectrometer (ESCALAB, Beijing, China).

[0053] Measurement of light transmittance of SUSC coating surface

[0054] The transmittance of the USC coating surface was measured using a UV-Vis spectrophotometer (UV-2600, Shimadzu, Japan). SUSC was sprayed onto a glass slide (7.5 cm × 2.5 cm), with the original glass slide serving as a control. The transmittance of air was set as the baseline for the test. The test wavelength range was 400 nm to 2500 nm.

[0055] Surface wettability test

[0056] Contact angle and slip angle were measured using a dynamic / static optical contact angle meter (SL250, KINO, USA). SUSC was coated on a 7.5cm × 2.5cm glass slide, with a liquid volume of 10μL measured each time. After the droplet stabilized, a side view image was captured using a camera. For the measurement of the slip angle, a motor-controlled rotatable test platform was used to change the surface angle, and the rotation angle was fed back to the computer in real time. The slip angle (θr) is the angle of inclination of the surface when a droplet of a certain volume (10μL) is about to roll on an inclined surface. When a liquid (10μL) rolls on a solid surface, due to the energy barrier at the droplet's front interface, there is an unequal contact angle before (θa) and after (θr), a phenomenon called the hysteresis contact angle (H). θ ).

[0057] Surface energy measurement

[0058] The surface energy (SE) of different coatings was calculated using DI water and dithiomethane on a CAM 200 optical contact angle goniometer (KSV Instruments Co., Ltd., Helsinki, Finland) at 25°C using the Owens-Wendt-Rabel-Kaeble (OWRK) method.

[0059] Surface lubrication performance test

[0060] The surface lubrication performance was characterized by testing the sliding speed of a water droplet on an inclined coating surface (8°). Video footage of the water droplet sliding across the inclined coating surface was obtained using a digital camera (Sony, FDR-AX60, Japan). The sliding time of the droplet from the starting point to the bottom of the slope was measured using a timer and video editing software (Pr). The sliding speed of the droplet was calculated based on the length of the slope path. The average value was taken as the droplet's sliding speed.

[0061] Surface temperature test

[0062] The sample coated on a 5cm × 5cm paulownia wood board was placed on a vacuum insulating plate above the ground (0.7m) to prevent heat conduction from the ground. Temperature was measured using a thermocouple data logger (Testo 176). Simultaneously, thermal measurements were performed on a blank copper plate under the same test conditions for comparison. Continuous infrared images of the SUSC were obtained by taking images at a fixed distance using a handheld thermal infrared imager (UT160H Unit-T, Shenzhen, China).

[0063] Results and Discussion

[0064] SUSC composition and coating surface

[0065] A typical solid smooth surface was prepared with a light transmittance close to that of glass (nearly 100%). Figure 1 Figure S2a shows the flat, smooth surface of the SUSC coating. It remains remarkably uniform and smooth even under magnification. EDS results indicate a uniform distribution of carbon, oxygen, and fluorine elements on its surface. Figure 1 b, S2b, c), which are necessary for the anti-slip performance of SUSC surfaces. An ultra-thin coating with a thickness of approximately 1.5 μm was obtained using a common spraying method. Figure 1 c). The ultra-thin structure is more advantageous for its optical transparency and heat dissipation. Furthermore, SUSC coatings can be successfully manufactured on almost all types of water-insoluble substrates, such as glass, silicon, ceramics, metals, and plastics. It is also suitable for coating electronic components. The rough texture of the SUSC surface can be observed using AFM, such as... Figure 1 As shown in d, almost no change in roughness was observed. The low RMS (1.76 nm) of the SUSC surface further confirms its low surface roughness at the nanoscale, with no aggregation.

[0066] To further investigate the composition of SUSC, the FTIR spectra of PFDA and the final polymerization product are as follows: Figure 1 f and Figure S1 are shown. 1410cm -1 The peak (CH deformation peak of vinyl β-carbon) disappears at 1730 cm⁻¹. -1(carbonyl stretching peak) and 810 cm⁻¹ -1 The weakening intensity of the bending vibration peak (at the unsaturated olefin) confirms the polymerization of monomers to form SUSCs. Furthermore, the absence of C=C bonds in SUSCs indicates that the acrylic acid monomers reacted completely. These results also confirm that SUSCs have a lower surface energy due to the CF bonds in their molecular structure. Figure 1 The high atomic ratio between fluorine and oxygen indicates a significant enrichment of perfluoroalkyl side groups on the coating surface. Previous studies have shown that perfluoroalkyl side chains containing more than eight -CF2 units exhibit a pronounced tendency to crystallize in highly ordered smectic liquid crystal B phases. In this case, the terminal -CF3 groups are arranged in a uniform hexagonal pattern on the SUSC surface. Figure 1 (g insertion). This structural feature facilitates the minimization of surface free energy and shields the electrical effects of polar groups. Consequently, the low interaction between the surface and the various contacting liquids results in a completely hydrophobic and smooth surface with self-cleaning properties.

[0067] SUSC's transparency and self-cleaning properties

[0068] The light transmittance of SUSC was tested and compared with that of uncoated glass. Figure 2 As shown in Figure a, within the wavelength range of 400–2500 nm, the transmittance curves of SUSC-coated and uncoated glass completely overlap. Furthermore, the SUSC coating can still be seen on a 5×5 cm glass substrate. Optical photographs of SUSC coating on large-size glass substrates (5 cm × 5 cm) demonstrate that the coating can be scaled up without affecting its transparency.

[0069] Figure 2 In Figures b, c, and d, it is shown that water and oil droplets (n-dodecane) can be easily removed from the SUSC-coated glass surface without leaving any residual film. Water and oil droplets were observed to slide off the surface at an angle of 12° within approximately 1.5 seconds without leaving any trace. SUSC was compared with two other typical low surface energy materials, polydimethylsiloxane (PDMS) and polyvinylidene fluoride (PVDF). Water could not slide along the surfaces of PDMS and PVDF, even though PDMS and PVDF are considered widely used hydrophobic materials.

[0070] These results confirm that the SUSC coating possesses an excellent fully hydrophobic smooth surface with superior self-cleaning properties and resistance to water and oil contamination. In terms of water resistance, the SUSC coating exhibits similar characteristics to superhydrophobic surfaces, but its waterslip angle is higher.

[0071] SUSC surface wettability

[0072] To observe the trajectory of the water droplet on top of the SUSC, a high-speed camera at 7400fps was used to capture the droplet's motion. When the droplet contacts the SUSC surface at an 8° angle, it begins to slide and diffuse. At 20ms, a disc-shaped pattern with the maximum diffusion diameter is formed, similar to the droplet bouncing on the superhydrophobic coating surface. The droplet continues to move forward approximately 1 cm within 360 milliseconds. Figure 3 (a)

[0073] The surface energies of SUSC-coated, PDMS, and uncoated glass were also tested. Compared to uncoated glass and PDMS, the fluorine enrichment on the SUSC surface exhibited lower surface energy. This was accompanied by lower hysteresis contact angle (HCA:H) and sliding angle (SA:θr). Figure 3 (b, c) results in a dynamically smooth liquid surface with low SE, low surface roughness, and good uniformity. Therefore, the contact angles Hpe and θr of SUSC are only 10°, far lower than those of PDMS (contact angles Hpe and θr ≈ 70°). Figure 3 (d).

[0074] In addition, a high-temperature steam resistance test was conducted. During the high-temperature steam fumigation process, ordinary copper was covered by water droplets condensing and forming a layer. Figure 3 (h,i,j), but on the SUSC-coated copper sheet, the water mist condensed into droplets and slid off within 3 seconds. After 6 seconds, most of the copper sheet surface was clean. Figure 3 (e, f, g). High-temperature steam shock tests show that the SUSC coating remains intact and exhibits good anti-slip properties even under continuous high-temperature steam shock. Evaporated water molecules gradually condense into droplets upon contact with the SUSC surface. These droplets then coalesce and detach from the surface. In contrast, the same phenomenon is not observed on smooth copper sheets.

[0075] Self-cleaning properties of SUSC coating

[0076] Smooth surfaces are widely used to prevent contamination because coatings shield potential contaminant contact. Furthermore, contaminants can easily remain on smooth surfaces with low affinity under external forces. Therefore, the anti-adhesion properties of SUSC were tested using selected contaminants, including TiO2 nanoparticles (~20 or 200 nm), SiO2 nanoparticles (~1 μm), and gravel particles (~200 μm). Figure 4 a). TiO2 nanoparticles and SiO2 microparticles of different particle sizes (2 mL) were dropped onto uncoated glass and SUSC at a 45° angle. Surface contaminants were observed using scanning electron microscopy. Without water rinsing, almost no contaminant residue remained on the SUSC. Figure 4 (f, g, h). Further statistical analysis of residual contaminants on the SUSC surface confirmed the self-cleaning ability of SUSC. Figure 4 (See insets for f, g, and h). Elemental fractions before and after contamination show that no contaminating elements were found on the SUSC-coated surface. However, a significant amount of residue was present on the uncoated glass. Figure 4 (in the middle, b, c, d and illustrations).

[0077] The above results demonstrate that the smoothness of SUSC can resist micron- and nano-sized contaminants. Gravel (200 μm) laid on ordinary and coated glass was rinsed with water at a 10° angle. The gravel on the SUSC was easily washed away by water. Figure 4 i), while a large amount of gravel remained on the uncoated glass. Figure 4 e). This proves that a large number of pollutants can be easily removed without any residue.

[0078] Thermal properties of SUSC coating

[0079] To understand the heat transfer performance of the SUSC coating, the temperature distribution of the coating at its base was recorded when it was heated by a heat source. For example... Figure 5 As shown in Figure a, the temperature distribution of the SUSC coating (approximately 1.5 μm thick) is uniform over a 3-minute interval. However, due to the poor thermal conductivity of the PU layer, it takes 183 seconds for the copper sheet temperature to decrease by 10°C. Using a PU coating as a radiative cooling layer in electronic devices may lead to localized high temperatures, potentially causing damage. The results indicate that the sample center temperature only decreased from the initial 60°C to 50°C after 3 minutes, demonstrating the poor thermal conductivity of the PU coating. The SUSC coating significantly reduced the coating temperature from 60°C to 50°C, a reduction of 10°C, which is attributed to the thermal radiation properties of SUSC.

[0080] The SUSC coating exhibits a significantly more uniform temperature distribution. It took only 146 seconds for the temperature to drop from an initial 60°C to 50°C. Compared to the PU coating, the SUSC coating demonstrates improved temperature uniformity and heat dissipation. Figure 5 As shown in b, the cooling rate of the SUSC-coated copper sheet is significantly slower than that of the PU-coated copper sheet. Furthermore, the durability of the SUSC coating was evaluated through temperature cycling tests (heating to the same temperature, followed by cooling at room temperature), such as... Figure 5 As shown in c. After 13 cycles, the SUSC coating exhibited good cooling performance.

[0081] The most important characteristic of SUSC coatings is that they form an ultra-thin coating on the substrate. This makes them an ideal candidate for waterproof packaging of small, precision electronic devices. The coating effectively protects electronic components from water, oil, and other contaminants, while maintaining the functionality of the electronic equipment under varying operating conditions. Figure 6 'a' is a diagram illustrating the working principle of a SUSC-coated LED lamp in NaCl solution. (See diagram for example.) Figure 6 As shown in Figure b, an LED light was connected to a battery with a wire and then placed in a 1 mol / L NaCl solution. The uncoated bulb failed to work in the NaCl solution due to a short circuit in the wire. In contrast, the SUSC coating ensured that the LED light worked in the NaCl solution. Figure 6 As can be seen from d, the copper wire is protected by the outer layer of the SUSC coating, further verifying the excellent waterproof performance of SUSC. Larger areas and complex electronic devices can be coated using spraying methods. For example... Figure 6 As shown in Figure c, after applying a SUSC coating to the circuit board, the electronic lamp can operate underwater, and the ultra-thin SUSC coating does not increase the thickness or weight of the electronic components.

[0082] Example 2

[0083] Preparation of solid smooth coating

[0084] 8 mL of perfluoro-1,2-dimethylcyclohexane and 3 mL of hexafluoropropylene dimer were added to a 100 mL round-bottom flask and magnetically stirred. After stirring at room temperature for 30 minutes, 0.05 g of perfluorodecyl acrylate and 0.04 g of isobornyl acrylate were added to the mixture. The mixture was stirred at room temperature for 15 minutes. 0.02 g of azobisisobutyronitrile (AIBN) was added dropwise to the mixture, allowing perfluorodecyl acrylate to crosslink and polymerize with isobornyl acrylate at 63 °C for 1.8 h. After the reaction, 5 mL of the resulting suspension was spin-coated onto a metal substrate, and then rapidly cured at room temperature for 60 s to form an ultra-smooth, pure solid surface.

[0085] One drop of the prepared suspension was placed on a metal substrate, and then it cured rapidly at room temperature for 60 seconds. Figure 7 As shown.

[0086] Example 3

[0087] Preparation of solid smooth coating

[0088] 7 mL of perfluoro-1,2-dimethylcyclohexane and 3 mL of hexafluoropropylene dimer were added to a 100 mL round-bottom flask and magnetically stirred. After stirring at room temperature for 30 minutes, 0.02 g of perfluorodecyl acrylate and 0.03 g of isobornyl acrylate were added to the mixture. The mixture was stirred at room temperature for 15 minutes. 0.01 g of azobisisobutyronitrile (AIBN) was added dropwise to the mixture, allowing the perfluorodecyl acrylate to crosslink and polymerize with the isobornyl acrylate at 65 °C for 2 h. After the reaction, 5 mL of the resulting suspension was spin-coated onto a metal substrate, and then rapidly cured at room temperature for 65 s to form an ultra-smooth, pure solid surface.

[0089] Comparative Example 1

[0090] The difference from Example 2 is that the perfluoro1,2-dimethylcyclohexane (7 mL) and hexafluoropropylene dimer (3 mL) are replaced with 11 mL of ethanol, while all other aspects are the same as in Example 2.

[0091] When the prepared coating is dropped onto a metal substrate, it is difficult for the coating to cure at room temperature. Figure 7 As shown, the applied coating did not cure after 20 minutes at room temperature.

[0092] Comparative Example 2

[0093] The difference from Example 2 is that perfluoro1,2-dimethylcyclohexane (7 mL) and hexafluoropropylene dimer (3 mL) are replaced with 11 mL of ethyl acetate, while all other aspects are the same as in Example 2.

[0094] When a drop of the prepared coating is placed on a metal substrate, the coating is difficult to cure at room temperature. Figure 7 As shown, the applied coating did not cure after 20 minutes at room temperature.

[0095] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a self-cleaning, waterproof, and heat-dissipating coating, characterized in that: The steps include the following: Mix perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer at 20-35°C; After the reaction is complete, perfluorodecyl acrylate and isobornyl acrylate are added to the mixture and stirred at 20-35℃. After stirring, AIBN is added to the reaction system and heated to allow perfluorodecyl acrylate and isobornyl acrylate to crosslink and polymerize, thus obtaining the coating. The mass ratio of perfluoro1,2-dimethylcyclohexane, hexafluoropropylene dimer, perfluorodecyl acrylate and isobornyl acrylate is 10-15:4-6:0.01-0.05:0.01-0.

05.

2. The method for preparing the self-cleaning, waterproof, and heat-dissipating coating according to claim 1, characterized in that: The mass ratio of perfluorodecyl acrylate to AIBN is 2-4:

1.

3. The method for preparing the self-cleaning, waterproof, and heat-dissipating coating according to claim 1, characterized in that: The reaction of perfluoro1,2-dimethylcyclohexane and hexafluoropropylene dimer was carried out at 20-35°C for 20-40 minutes with stirring.

4. The method for preparing the self-cleaning, waterproof, and heat-dissipating coating according to claim 1, characterized in that: After adding perfluorodecyl acrylate and isobornyl acrylate to the mixture, the reaction time is 10-30 min.

5. The method for preparing the self-cleaning, waterproof, and heat-dissipating coating according to claim 1, characterized in that: The crosslinking polymerization of perfluorodecyl acrylate and isobornyl acrylate takes place at a temperature of 55-65℃ for 1.5-2.5 hours.

6. A self-cleaning, waterproof, and heat-dissipating coating, characterized in that: It is prepared by any one of the preparation methods described in claims 1-5.

7. The application of the self-cleaning, waterproof, and heat-dissipating coating of claim 6 in the coating and encapsulation of electronic devices.

8. The application according to claim 7, characterized in that: When coating and encapsulating electronic devices, the coating is applied to the surface of the electronic device and cured at 20-35°C.

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