Preparation of PVDF-HFP@FAS electrospun fibrous film with special wettability and the research of its oil-water separation performance

In this paper, the superhydrophobic and superoleophilic poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) fibrous films were successfully fabricated via electrospinning technique combined with 1H, 1H, 2H, 2H-perfluorodecy-ltrimethcxysilane (FAS) fluorination. Meanwhile, the oil-water separation capacity of the superhydrophobic and superoleophilic 1H, 1H, 2H, 2H- perfluorodecyltrimethcxysilane modified poly-(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP@FAS) nanofibrous films were tested and analyzed. Accordingly, scanning electron microscopy(SEM), contact angle (water contact angle (WCA), oil contact angle (OCA)), et al, were used to characterize the prepared samples. The results show that the diameter of PVDF-HFP nanofibers are ranged from 100 nm to 500 nm. After FAS fluorination, the water contact angle of as-prepared samples increase, and oil contact angle decrease, which demonstrate that due to fluorination, the samples are more hydrophobic and oleophilic. Furthermore, the oil-water separation capacity of all prepared nanofibrous films was measured. It can be seen that as the fiber diameter decreases, the oil-water separation efficiency is improved. Moreover, the PVDF-HFP@FAS samples show higher oil-water separation efficiency. The maximum oil-water separation efficiency can reach to 97.50 ± 2.22%. Such superhydrophobic/superoleophilic fibrous materials can be used as an oil-water separating fibrofelt and exhibit great potential in this field.