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CN-122013135-A - Preparation method of super-hydrophilic surface constructed by ordered microstructure and coating thereof

CN122013135ACN 122013135 ACN122013135 ACN 122013135ACN-122013135-A

Abstract

The invention relates to a preparation method of a super-hydrophilic surface constructed by an ordered microstructure and a coating thereof, belonging to the technical field of preparation of surface functionalized coatings. The method comprises the steps of adopting PECVD to deposit HMDSO polymer on the surface of a substrate to form an initial organic silicon deposition layer, then closing ventilation and plasmas for a period of time to regulate and control the density of surface active groups, depositing TMCTS polymer on the surface of the obtained organic layer, enabling a chip structure formed after TMCTS plasma activation to be deposited on the surface active sites preferentially to form an ordered cellular microstructure, and carrying out oxygen plasma modification and hydrophilic polymer molecular chain grafting on the surface with the microstructure to construct the super-hydrophilic functional layer. According to the invention, the chemical characteristics, active sites and local selective growth of the precursor are cooperatively regulated, so that the ordered construction of the surface microstructure is realized, and the coating with high light transmittance, long-term stable super-hydrophilicity and excellent anti-fog performance is obtained through acrylic acid grafting.

Inventors

  • YE YUMIN
  • LI YU
  • WANG ZHENBO
  • XU HE

Assignees

  • 宁波大学
  • 浙江省白马湖实验室有限公司

Dates

Publication Date
20260512
Application Date
20260409

Claims (10)

  1. 1. An ultra-hydrophilic surface coating constructed by ordered microstructures, wherein the coating comprises, from a substrate to the outside, in order: Depositing an initial organosilicon smoothing layer containing Si-O-Si/Si-OH bonds on the surface of the substrate by adopting a PECVD mode and taking HMDSO and O 2 as reaction gases; An ordered cellular or island-like microstructure layer formed on the initial silicone smoothing layer, the microstructure layer being composed of a silicone polymer containing Si-O-Si bonds, the microstructure unit size being 0.3 to 1.2 μm, the microstructure units being ordered and distributed on the initial silicone smoothing layer, and A hydrophilic polymer layer anchored to the surface of the microstructured layer by chemical bonding.
  2. 2. The ordered microstructure structured super-hydrophilic surface coating of claim 1, wherein the hydrophilic polymer layer is an acrylic polymer hydrophilic layer, and carboxyl groups in the acrylic polymer hydrophilic layer are combined with water molecules through hydrogen bonds, so that super-hydrophilic performance is imparted to the coating.
  3. 3. The super-hydrophilic surface coating constructed by ordered microstructure according to claim 2, wherein the thickness of the hydrophilic layer of the acrylic polymer is 5-50nm, and the hydrophilic layer is PECVD-treated to form a stable network with a crosslinked structure.
  4. 4. A method of preparing a superhydrophilic surface coating constructed with ordered microstructures according to any one of claims 1-3, comprising the steps of: (1) Adopting a PECVD mode, taking HMDSO and O 2 as reaction gases, and forming an initial organic silicon deposition layer containing Si-O-Si/Si-OH on the surface of the substrate; (2) After the deposition in the step (1), stopping introducing the reaction gas and the precursor, turning off a plasma power supply, and keeping the substrate in a vacuum environment for 1-3 min to reduce the number and density of active groups on the surface of the deposition layer; (3) PECVD deposition is carried out on the surface treated in the step (2) by taking TMCTS and O 2 as reaction gases under the condition that the power of a plasma power supply is 100-200W, and the reaction anchoring between free radicals and ion fragments generated after the TMCTS is activated by utilizing plasma and active sites is carried out, so that the TMCTS preferentially nucleates and grows on the active sites to form ordered cellular or island microstructures; (4) And (3) performing oxygen plasma activation treatment on the surface with the microstructure obtained in the step (3), and introducing hydrophilic polymer monomers to perform plasma graft polymerization to construct the super-hydrophilic functional layer.
  5. 5. The method for preparing a superhydrophilic surface coating constructed with ordered microstructures according to claim 4, wherein in the step (2), the substrate is kept to stand in a vacuum environment for 2min.
  6. 6. The method for preparing a super-hydrophilic surface coating constructed by ordered microstructures according to claim 4, wherein in the step (1), the flow ratio of HMDSO to O 2 is 2:1, the deposition pressure is 40-70Pa, and the deposition time is controlled to be 2-5min.
  7. 7. The method for preparing a super-hydrophilic surface coating constructed by an ordered microstructure according to claim 4, wherein in the step (3), the flow ratio of TMCTS to O 2 is 1:1, the deposition pressure is 40-80Pa, and the deposition time is 5-15min.
  8. 8. The method for preparing the super-hydrophilic surface coating constructed by the ordered microstructure according to claim 4, characterized in that the hydrophilic polymer monomer in the step (4) is acrylic acid.
  9. 9. The method for preparing the super-hydrophilic surface coating constructed by the ordered microstructure according to claim 8, wherein the method for constructing the super-hydrophilic functional layer in the step (4) is characterized by comprising the steps of firstly introducing O 2 into a cavity for plasma activation treatment, then introducing mixed gas of acrylic acid and O 2 for graft polymerization under a discharge condition, finally closing O 2 , continuously introducing acrylic acid gas for subsequent reaction, wherein the ratio of the mixed gas of the acrylic acid and the O 2 is 2:1, and the grafting polymerization temperature is 50-80 ℃ and the time is 10-20min.
  10. 10. The method for preparing a superhydrophilic surface coating constructed with ordered microstructures according to claim 4, wherein in the step (1), the substrate comprises any one of silicon wafer, glass, ceramic, metal, and plastic.

Description

Preparation method of super-hydrophilic surface constructed by ordered microstructure and coating thereof Technical Field The invention belongs to the technical field of preparation of surface functionalized coatings, and particularly relates to a preparation method of a super-hydrophilic surface constructed by an ordered microstructure and a coating thereof. Background The transparent antifogging coating is widely applied to the fields of optical lenses, vehicle windows, cameras, optical parts for navigation equipment and the like, and particularly in environments with high humidity and large temperature difference, such as automobile windshields, display screens of electronic equipment, aviation instruments and the like. The super-hydrophilic anti-fog coating has the main functions of promoting water film spreading by reducing the surface contact angle, preventing water drops from forming on the surface and avoiding vision blurring caused by light scattering. However, conventional superhydrophilic coatings, while effective at eliminating surface fogging initially, have significant limitations during long-term use. Such coatings generally rely on surface-introduced hydrophilic groups (e.g., -OH, -COOH) to achieve ultra-hydrophilicity, but these hydrophilic groups are susceptible to oxidation, adsorption of impurities in the air, or chemical degradation over time, resulting in gradual decay of coating properties, and difficult long-term maintenance of anti-fog effects. Particularly for smooth and unstructured super-hydrophilic surfaces, the wetting and spreading process of water drops after contacting the surface is mainly dominated by surface chemical action, and the effective regulation and control of the surface structure on the liquid interface is lacking. When the hydrophilic groups on the surface pollute or locally fail, the water drops shrink locally, and a continuous and stable water film is difficult to form. Such superhydrophilic surfaces, which rely solely on chemical composition and lack structural synergy, are difficult to maintain in a long-term stable superhydrophilic state in complex environments. The micro-nano structure is constructed on the surface, so that more capillary channels and continuous spreading paths can be formed, the conversion speed of water drops to a water film is accelerated, meanwhile, the micro-nano structure has a certain pinning effect on a liquid interface, the formed water film is not easy to crack or retract when disturbed, and the spreading stability of the water film is effectively enhanced. However, the larger height fluctuation and the dimension distribution difference of the unordered microstructure can introduce a light scattering effect, so that the light transmittance is reduced, and the application requirement of the optical device on high transparency is difficult to meet. Compared with a disordered microstructure, the ordered microstructure has regular arrangement and space frequency with specific distribution, so that the randomness of the surface morphology can be reduced, the multi-angle scattering and the increase of haze caused by random height fluctuation and scale distribution can be effectively avoided, and the high transparency of the material is maintained. In addition, the ordered microstructure can form a refractive index gradient layer between air and the substrate, so that light reflection loss at an interface is reduced, and the improvement of transmittance is realized while low scattering is ensured. Therefore, the ordered microstructure surface not only does not reduce the transmittance, but also helps to improve the overall optical performance, which provides a structural basis for the application of the ordered microstructure surface in transparent anti-fog coatings and optical devices, and is expected to realize a more stable and durable anti-fog surface. However, the existing methods for preparing structured surfaces have certain limitations. Based on top-down processing technologies such as photoetching and template methods, regular structures can be obtained, but the process flow is complex, the cost is high, the adaptability to the size and the shape of the substrate is limited, the structure depends on physical forming, strong chemical bonding is absent between the structural layer and the substrate, the structural damage is easy to occur under the action of mechanical abrasion or environmental stress, and the large-scale application is not facilitated. Meanwhile, the methods such as spraying, dip coating and the like from bottom to top are simple in process and high in applicability, but the film forming process is influenced by factors such as liquid drop accumulation, solvent volatilization and the like, the structural growth has high randomness, ordered microstructure regulation and control are difficult to realize, and particularly, a coating with high transparency is difficult to form in actual production. The chemical vapo