Fabrication And Interface Properties Of Fabrics With Special Wettability Modified By Fluorine/silicone Chemicals

Wettability is one of the most important properties of material surface.With the increase of the people’s demands,the prospect of the materials with special wettability in the actual production and daily life is brilliant.Among these,the self-cleaning surface,drag reduction as well as the micro-robots and sensors working on liquid surfaces have aroused broad attention due to their unique performances.However,many existing liquid-repellent materials are lack of mechanically durability,leading to the fact that their stability in applications encounters a great challenge.Besides,thanks to the fabrications and applications of materials with asymmetric wettability inspired by nature,there are great progress in membrane separation,health care,and industry.Whereas,there are not enough in-depth studies about the functionalization of this kind of materials and their surface performances,which will limit their further developments.In this study,by introduction of the fluorine/silicone components which usually exhibit low surface energy,several kinds of fabrics with different special wettability and mechanically durability have been fabricated,and the properties of their interfaces were studied in detail.Liquid-repellent PET fabrics with mechanically durability were prepared by the assistance of Schiff-base reaction.Due to the covalent bonds connected among the components,the modified PET fabrics could maintain great liquid repellency after 20 times of sand impact test,500 times of abrasion test,as well as being abraded by sand paper repeatedly to destroy the fabric.Various liquids,such as water and other organics,could slide off from the surface easily.Also,the prepared fabric could not only float on water or oils,but also hold up things on its surface without sinking.The fabricated fabrics and the results presented here could have more potential values in the development of soft micro-devices working on liquid surfaces,especially on high viscous liquid surfaces or under the environment with harsh conditions.Then,plasma grafting polymerization and the combined method of reversible addition fragmentation chain transfer(RAFT)polymerization and Click-chemistry were adapted in the fabrication of different kinds of pH-responsive Janus cotton fabrics.By means of plasma polymerization,it would take a short time to prepare pH-responsive Janus fabrics.And thanks to the protonation and deprotonation effect,after being treated with acid/basic treatments,the pH-responsive side of the fabrics would transform between hydrophobicity and hydrophilic.The adaptation of RAFT polymerization and Click-chemistry could be of help to design and control the polymer structure.By using different responsive monomers,two kinds of Janus cotton fabrics with different pH-responsive properties were fabricated.Furthermore,the results showed that the introduction of the segments with fluorine would improve the hydrophobicity of the pH-responsive side,which was attributed to the existence of synergistic effect.These materials are expected to be applied in the smart membrane separation and switchable membranes.