Electrospinning of polyvinylidene fluoride membranes: effect of membrane composition and fabrication conditions

Membrane fabrication by the electrospinning can provide tunable structure membranes with interconnected pores, large surface area, and high porosity. This study focuses on studying the effect of different membrane compositions (i.e., polymer concentration and inorganic additives) and electrospinning conditions (i.e., internal needle diameter, tip to collector distance, and feed flow rate) on the quality of polyvinylidene fluoride (PVDF) flat sheet membrane. A homogeneous dope solution was prepared by dissolving the PVDF in a mixture of dimethylacetamide (DMAc) and acetone. By using a scanning electron microscope (SEM), the electrospinning conditions producing beadles fibers are as follows: 16 wt% polymer concentration, 0.004 wt% LiCl concentration, 0.51 mm internal needle diameter, 15 cm tip to collector distance, feed flow rate of 1 ml/hr. Further analysis was conducted by using Fourier Transform Infrared Spectrometer (FTIR) and X-Ray Diffraction (XRD) to assess the impact of electrospinning on fibers elemental composition. Additionally, static water contact angle, porosity, fiber diameter, and pore size measurements reveal the formation of submicron hydrophobic fibers with random alignment.