Highly Durable and Robust Superhydrophobic/Superoleophilic Cotton Fabric with Well-designed Roughness for Oil/Water Separation

Herein we report a simple and reproducible method for fabricating highly durable and robust superhydrophobic and superoleophilic cotton fabrics via simultaneous radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modifications with aminopropyltriethoxysilane and hexamethyldisilazane. The chemical structure and the surface topography of the pristine and the modified cotton fabrics were investigated in detail by ATR-FTIR, XPS, and Si-29 NMR, and a grafting layer was successfully immobilized onto the surface of the cotton fabric by forming covalent bonds. Multi-dimensional surface roughness was created by combining micro-sized fibers of the cotton fabric, nanoscaled protuberances of the grafting chain, and molecular level spherical projection points of silicon methyl. The superhydrophobic cotton fabric exhibited long-term stability, ultra-high durability and robustness, and maintained its properties even after 25 wash cycles. The fabric also showed excellent water repellency with a water contact angle of 153 degrees and a high efficiency of oil/water separation (98 %). The superhydrophobic/superoleophilic cotton fabric developed in the present work exhibits important potential applications in superhydrophobic textiles and oil/water separation.