Fabrication of durable superhydrophobic surfaces of polyester fabrics via fluorination-induced grafting copolymerization

Abstract Nowadays, the construction of a hydrophobic layer on the surface of the fabric to achieve durable superhydrophobicity is still facing challenge due to the weak interfacial interaction between hydrophobic layer and fabrics. Herein, a novel surface design strategy is proposed on commercial polyester (PET) fabrics by in-situ fluorination-induced radial polymerization. Two kinds of free radicals are detected by electron paramagnetic resonance on fluorinated PET fabrics and fluororadicals are found to be more likely to initiate polymerization. Hyperbranched nano silica with double bonds are covalently grafted to the surface by radial initiated grafting copolymerization with trifluoroethyl methacrylate and divinylbenzene to provide a nanostructure. It is confirmed that the natural hydrophobic chemical composition and the micro/nanostructures provided by the fabric and silica synergistically construct a superhydrophobic surface having water contact angle and shedding angle of 161° and 8°, respectively, which shows good performance for separating water-in-oil emulsions. More importantly, with covalent bonding originated by fluorination at the interface, the obtained superhydrophobic fabrics shows outstanding durability and water repellency that can endure different chemicals, long time exposure to Uv irradiation, 20 laundering cycles and 100 abrasion cycles.