Liquid-like PDMS brushes coating with low adhesion to droplets are significant in both fundamental research and practical application. Covalent grafting is a common strategy to prepare PDMS brushes with low adhesion to diverse liquids in a wide range of surface tensions, but it is only suitable for high active inorganic substrates. Casting of mixtures containing PDMS can solve this problem; however, homogeneity and low adhesion cannot be guaranteed. Here we report a simple method by step-by-step spraying for preparing PDMS brushes, which is suitable for both substrates. Droplets with a wide range of surface tension can slide off the coating with a sliding angle less than 10°. Research results indicate that the polyamine with flexible molecular chain and high functionality is beneficial for brushes coating with high grafting density and excellent surface lubricity. Finally, good stability and diverse applications in fouling resistance, self-cleaning, anti-bursting, etc. are also demonstrated.
Tianqi Wang,Hongrui Yao,Na Wang,Yangsong Wang,Fei Wang
Superhydrophobic coatings have attracted significant attention for their potential in anti-icing applications. However, their practical application is often hampered by inherent limitations, such as mechanical durability and insufficient de-icing performance. In this study, a functional filler (ODA/MnO 2 @PDA-SiO 2 , OMPS) is synthesized by simple grafting and redox reaction, and a robust superhydrophobic low-adhesion anti-icing coating (OMPS-PDMS/E51) is prepared through spraying. The OMPS-PDMS/E51 coating surface shows a uniformly distributed concave-convex structure with a roughness value of 33.209 μm. This fine micro-nano structure makes the water contact angle of the coating surface as high as 157.1° and the rolling angle as low as 4.6°, indicating that the coating has excellent superhydrophobicity. Meanwhile, the coating surface is in a low water adhesion Cassie-Baxter state, so it has good antifouling and self-cleaning properties. Additionally, Cassie-Baxter wetting mode can minimize the contact between the coating and water, thereby inhibiting the formation and anchoring of ice core, so the freezing delay time of the OMPS-PDMS/E51 coating is up to 358 seconds and the ice adhesion strength is as low as 26.3 KPa. Notably, the OMPS-PDMS/E51 coating also exhibits the characteristics of active de-icing, which can rapidly heat up the coating surface through photothermal conversion, such as its surface temperature can reach 82.9 °C after infrared irradiation for 400 seconds, and the ice formed at -20 °C on the coating can melt within 144 seconds. These properties highlight the OMPS-PDMS/E51 coating’s potential for long-term anti-icing and de-icing applications in harsh environments.
Xinlei Wu,Jun Yao,Yingjie Guo,Sijia Zheng,Yifang Mi,Zhihai Cao
Durable antibacterial surfaces are often required high bactericidal ability and low bacterial adhesion property, but the potent bactericidal surfaces, especially based on the contact bactericidal mechanism, are often paradoxically intended to attract bacteria to adhere. In this work, a delicate balance between the potent contact bactericidal action and low bacterial adhesion was successfully achieved in quaternized fluoropolymer/SiO 2 composite films (QFP/SiO 2 CFs) through judicious selection of a common fluorinated monomer, a common quaternary ammonium monomer, and a common inert inorganic nanoparticle, to acquire suitable surface energy and chain mobility to ensure low bacterial adhesion, as well as to allow appropriate surface-exposed quaternary ammonium units to synergistically enhance the contact bactericidal action with the specific fluorinated side chains. The QFP/SiO 2 CFs were conveniently fabricated through miniemulsion polymerization and followed squeegeeing technique. The QFP/SiO 2 CF with an optimized composition exhibited extremely low initial adhesion of bacteria, potent contact bactericidal action, superior long-term antibacterial performance, easy sonication-assistant regeneration for multiple usage, and low cytotoxicity with non-leachable attribute. This work may guide the design and efficient fabrication of leaching-free durable antibacterial surfaces for biological applications, as well as provide an effective strategy to balance contact bactericidal action and low bacteria adhesion for durable antibacterial performance.
危险品化学品经营许可证（带存储）