Superhydrophobic fluorinated POSS-PVDF-HFP nanocomposite coating on glass by electrospinning

Fluorinated polyhedral oligomeric silsesquioxanes-poly(vinylidene fluoride-co-hexafluoro propylene) (fluoroPOSS-PVDF-HFP) nanocomposite mixtures are prepared by individually mixing two fluorinated POSS materials (FP8 and FPSi8) with PVDF-HFP solution and transparent superhydrophobic coatings on a glass substrate are produced by electrospinning. The fabricated superhydrophobic surface exhibits continuous, uniform and non-beaded nanofibers with a high water contact angle (157.3 degrees) and a low sliding angle (SA < 5 degrees). The superhydrophobic properties including surface energy, water contact angle, and contact angle hysteresis as well as the optical properties are studied by altering the wt% of fluoroPOSS in PVDF-HFP solution. It is observed that due to the increase in the viscosity of the solution, the diameter of the nanofibers increases with increase in the concentration of fluoroPOSS. It is also observed that as the concentration of fluoroPOSS in PVDF solution increases, the amount of fluorine content increases thereby the surface energy of the coating decreases (to around 10 mN m(-1)) leading to a superhydrophobic surface with low contact angle hysteresis (< 5 degrees). The optical properties of the coatings produced using FPSi8 fluoroPOSS-PVDF-HFP mixture are compared with those of FP8 fluoroPOSS, and the former is found to be more transparent due to its relatively high solubility in PVDF-HFP.