Fabrication Of Superwetting Cotton Fabric And Its Application In Oil/Water Separation

The discharge of oily sewage and frequent oil spill accidents have not only cause serious damage to water resources,but also a waste of resources.With the development of bionics and interface science,lots of superwetting materials with good separation ability have been fabricated and used in oil/water separation.It well-known that superwetting materials general have specific surface energy and rough structures.According to this principal,cotton fabrics which can be obtained easily in our daily life are used to fabricate superamphiphobic or underliquid superamphiphobic by vapor-liquid sol-gel method and thiol-ene click reaction.The applications of fabric in different field,especially in oil/water separation,were studied in this paper.The main contents are as follows:?1?A superamphiphobic cotton fabric was fabricated by quick and time-saving vapor-liquid sol-gel method to deposit silica with thiol?Si O₂-SH particles?and thiol-ene click reaction to graft 1H,1H,2H,2H-heptadecafluorodecyl methacrylate?FMA?.The durable fabric can repel hexadecane with surface tension as low as 27.5 m N/m.The Si O₂-SH particles can build rough structure and FMA can decrease the surface tension.Importantly,the fabric can keep high superamphiphobicity after 15 cycle laundry test,40 cycle tape-peeling test,24 h UV irradiation and immersion in different liquid?acid,base solution,cold and hot water?.After the fabric was prewetted by ethanol whose surface tension is 21.8 m N/m,it shows superhydrophilicity/underwater superoleophobicity and superoleophilicity/underoil superhydrophobicity and can be used for on-demand oil/water separation.The separation efficiency of the fabric was greater than 98%.Besides,the fabric also can be used in self-cleaning and antifouling application.?2?In order to better explore the application of superwetting materials in oil/water separation,we prepared and studied another material with different wetting property.Similarly,an underoil superhydrophobic and underwater superoleophobic cotton fabric was fabricated by vapor-liquid sol-gel method to deposit Si O₂-SH particles,follow by thiol-ene click reaction to graft hydrophilic 2-?dimethylamino?ethyl methacrylate?DMAEMA?.It shows an underoil water contact angle?UOWCA?of 162°and an underwater oil contact angle?UWOCA?of 162°.More importantly,the fabric can keep high UOWCAs and UWOCAs after immersion in organic liquid for 240 h,acid,base or Na Cl solution for 168 h.What is more,the fabric can used for on-demand oil/water separation,water-in-oil emulsion and oil-in-water emulsion separation and the relative separation efficiency are greater than 98%.