Nanofibers of polyvinylidene fluoride (PVDF) were prepared using solutions of PVDF with acetone and dimethylacetamide. The solutions were prepared at different concentrations (18, 21.5, and 25% wt) of PVDF. The nanofiber membranes were produced by using the Forcespinning (TM) method. Parameters such as the orifice size and spinneret angular velocity were varied. The produced membranes were characterized using scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction to determine the effect of varying parameters in the Forcespinning (TM) process on fiber diameter, bead formation, thermal stability, polymorphism, and morphology of the fibers and overall structure of the membrane. It was observed that polymer concentration played a key role in fiber and bead formation; at higher concentrations (such as 25 wt%), the fiber diameter increased but the bead formation decreased. The prepared composite membranes have potential applications on separators for Li-ion batteries, ultra filtration membranes, and proton conductivity membranes for fuel cells applications. POLYM. ENG. SCI., 2012. (C) 2012 Society of Plastics Engineers