Rheology-Guided Spinnability in Emulsion Forcespinning of Water-in-Oil Nanofibers: Influence of Surfactants and Internal Phase Concentration

This study explores the emulsion Forcespinning (FS) approach for fabricating nanofibers with a hydrophilic phase encapsulated within a hydrophobic polymer matrix. Key factors influencing fiber production and morphology, including the concentration of the internal water phase and the presence of ionic and nonionic surfactants, were systematically investigated. Additionally, the centrifugal spinnability of the emulsions was assessed using environmentally controlled dripping-onto-substrate (DoS) rheometry, correlating the observed extensional flow behavior and emulsion extensibility with fiber spinnability. The nanofibers were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. These findings offer critical insights for optimizing emulsion-based FS systems in fiber design, with significant potential for biomedical and food industry applications.