Sticky problems on surfaces from various foulants inhibit us from the access to clean toilets, hygiene medical ware, and high-efficient energy transfer. They vastly exist in most industrial, medical, and household interfaces, and they dramatically dysfunction the well-designed surface structures by sticking on them. In contrast, nature has provided us abundant examples of keeping surfaces clean, from duck feather to lotus leaf, to springtail skin, to pitcher plant rim, and to many other insect/animal surfaces. These examples share some common materials design principles for antifouling, particularly for solid repellency. With complex fouling conditions [1] on surfaces for various applications, it is critical to explore the mechanisms of solid-repllent natural surfaces and create effective antifouling coatings.
Inspired by the pilot whale skin, herein, we report the design of solid- and liquid-repellent coatings that can effectively repel a wide range of solid foulants. For example, the ice adhesion strength on such coatings was less than 1 kPa, at least 2 orders of magnitude lower than the state-of-the-art anti-icing materials. Further, we reveal a new strategy to significantly enhance the mechanical durability of such coatings by incorporating partially crosslinked lubricating chains within a durable polymer matrix. In particular, we fabricated partially crosslinked omniphobic polyurethane (omni-PU) coatings that can repel a broad range of foulants, comprised of both liquid and solid phases. The fabricated coatings are an order of magnitude more resistant to cyclic abrasion than current state-of-the-art slippery surfaces. Furthermore, through the integration of classic wetting and tribology models, we introduce a new material design parameter (K_AR) for abrasion-resistant polymeric coatings. This combination of mechanical durability and broad antifouling properties enables the implication of such coatings to a wide variety of industrial and medical settings, including wind turbine blades, heat exchanges, and antifouling robotics.
 

抗粘附,仿生,材料力学,蓝色能源