摘要

Integrated electrospun nanofibrous membrane was prepared by creating soldered junctions between nanofibers via a facile strategy. Polyacrylonitrile (PAN) mixed with poly(vinylidene fluoride) (PVDF) at different ratios of PVDF were prepared in N,N'-dimethyl formamide (DMF), then electrospun to fabricate PAN/PVDF membranes. PVDF can form microgels in DMF which slows down volatile speed of DMF and affects the solidification of PAN/PVDF nanofibers. The resulting membranes were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, dynamic water contact angle and tensile testing to confirm the morphology and mechanical properties. Soldered junctions were observed between nanofibers with the increase of PVDF content. These junctions made the membrane integrated and greatly enhanced tensile strength from 5.1 to 8.1 MPa (increased by similar to 60%) and tensile modulus from 49.4 to 117.9 MPa (increased by similar to 139%) without compromising porosity when the content of PVDF increased from 0 to 60 wt%.