Parbat Dibyangana, Gaffar Sana, Rather Adil Majeed, Gupta Aditi, Manna Uttam
Department of Chemistry , Indian Institute of Technology-Guwahati , Kamrup , Assam 781039 , India . Email:
Chem Sci. 2017 Sep 1;8(9):6542-6554. doi: 10.1039/c7sc02296d. Epub 2017 Jul 10.
The controlled modulation of both oil (under water) and water (in air) wettability is an emerging approach to develop several functional materials for various prospective applications including oil/water separation, anti-corrosive coatings, underwater robotics, protein crystallization, drug delivery, open microfluidics, water harvesting Here, we report a 'reactive' and covalently cross-linked coating through a facile and robust Michael addition reaction, which is suitable for the controlled and extreme regulation of both water and oil wettability in air and under water respectively. Along with extremes (super-philicity and super-phobicity) of water (in air) and oil (under water) wettability, this single multilayer construction was also able to display special liquid wettability (; extremely liquid repellent-but with controlled adhesive properties) both in air and under water, after strategic post chemical modifications, again through 1,4-conjugate addition reaction. The super-wetting properties in the materials were able to withstand various physical and chemical insults including adhesive tape test, sand drop test, and exposure to extremes of pH, salt, and surfactant contaminated aqueous media. Moreover, this approach also allowed the decoration of various flexible and rigid substrates (; wood, Al-foil, synthetic fabric ) with various bio-inspired wettability properties including (1) non-adhesive superhydrophobicity (lotus leaf), (2) adhesive superhydrophobicity (rose petal), (3) underwater superoleophobicity (fish scale) This single polymeric coating-which is capable of displaying several bio-inspired interfaces both in air and under water, even after harsh physical/chemical insults-would be useful in various prospective and relevant applications for practical scenarios.
对油（水下）和水（空气中）润湿性进行可控调节是一种新兴方法，可用于开发多种功能材料，以满足各种潜在应用需求，包括油水分离、防腐涂层、水下机器人技术、蛋白质结晶、药物递送、开放式微流控、集水等。在此，我们报道了一种通过简便且稳健的迈克尔加成反应形成的“反应性”共价交联涂层，该涂层分别适用于在空气中和水下对水和油的润湿性进行可控的极端调节。除了水（空气中）和油（水下）润湿性的极端情况（超亲水性和超疏水性）外，这种单一的多层结构在经过策略性的后化学修饰（同样通过1,4-共轭加成反应）后，在空气中和水下也能够表现出特殊的液体润湿性（即极端拒液但具有可控的粘附特性）。材料的超润湿性能够经受各种物理和化学损伤，包括胶带测试、沙滴测试以及暴露于极端pH值、盐和受表面活性剂污染的水性介质中。此外，这种方法还能够在各种柔性和刚性基材（如木材、铝箔、合成织物）上实现多种受生物启发的润湿性装饰，包括（1）非粘附性超疏水性（荷叶）、（2）粘附性超疏水性（玫瑰花瓣）、（3）水下超疏油性（鱼鳞）。这种单一的聚合物涂层即使在遭受 harsh物理/化学损伤后，仍能够在空气中和水下展现出多种受生物启发的界面，在各种实际场景的潜在相关应用中具有实用性。
