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In recent work, we demonstrated the successful fabrication of core-shell nanofiber composites with enhanced tensile, surface wetting and cytocompatibility properties via coaxial electrospinning using PLA and PVA. It has been shown that core/shell-structured PLA/PVA nanofiber mat has the hydrophilic benefits of PVA and the attractive biological properties of PLA. In this paper, we present detailed mechanical evaluation of the electrospun coaxial nanofiber mats under static, dynamic and creep loading. The core/shell-PLA/PVA nanofibers showed nearly 233% and 150% increase in tensile strength and ductility, respectively, compared to pristine PLA. Dynamic loading tests were employed to study the viscoelasticity of the coaxial core-shell composite nanofibers at various temperatures and frequencies. The results of the storage and loss moduli of the coaxial nanofibers suggested strong physical interaction between the PLA and PVA layers, that contribute to the observed good mechanical behaviour. The better creep resistance of the coaxial PLA/PVA nanofibers under axial loading compared to the pristine materials provides further evidence for the physical interaction between the two constituent materials. A simple linear viscoelastic model is used to quantify the evolution of creep strain in pristine and coaxial materials. This research may help to understand the physical relation between the observed viscoelastic behaviour and the internal structure of coaxial core/shell nanofibers of PLA and PVA. [ABSTRACT FROM AUTHOR]

Low stability in oil media and the hydrophobicity problems of the polysulfone electrospun membranes could be overcome in the present study. Synthesis of super-hydrophilic and highly stable in oil polysulfone electrospun nanofiber membrane was achieved by electrospinning of polysulfone solution containing NaOH nanoparticles followed by activation of the dried electrospun membrane by deposition of polyamide layer on the surface using m -phenylenediamine and 1,3,5-benzenetricarbonyl chloride. The introduced membrane has super-hydrophilicity characteristic (contact angle=3 o ), excellent stability in oil media and distinct performance in oil-water separation process. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-incorporated TiO 2 nanofibers was successfully synthesized via a simple and effective technique, electrospinning and applied as a working electrode for dye sensitized solar cells (DSSCs). The effects of graphene oxide on the structural and photoelectric conversion performance of the DSSCs were inspected by various analytical techniques. The results suggest that presence of graphene oxide increases the amount of dye absorption which leads to high migration of photoinduced electrons to the conduction band of the collection electrode and inhibition of electron recombination. Furthermore, the presence of graphene oxide improves the electron transport from the films to the fluorine doped tin oxide (FTO) substrates. Accordingly, remarkably enhanced power conversion efficiency of 4.52% was observed in case of utilizing 0.5 wt% graphene oxide-incorporated TiO 2 nanofibers as working electrode based DSSC which is higher than that of the conversion efficiency in case of pristine TiO 2 nanofibers (i.e. 1.54%). The high amount of graphene oxide content results in decrease the power conversion efficiency. Therefore, it can be claimed that graphene oxide-incorporated TiO 2 nanofibers as working electrode is a promising candidate for improving the performance of the DSSCs. [ABSTRACT FROM AUTHOR]