Development and evaluation of novel nanofibers based on mango kernel starch obtained by electrospinning

This work reports on the development of fibers based on natural mango kernel starch (MKS) with diameters in the nanoscalse by means of the electrospinning technique. MKS was extracted from mango kernels and two synthetic polymers, namely polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), were blended with MKS in order to improve its spinnability, obtaining MKS/PVA and MKS/PVP fibers with a 10 wt% of total polymer concentration. Several electrospinning conditions (voltage and flux) were tested in solutions of MKS concentrations ranging from 0 to 5 wt% for both group of fibers. The morphology of all the fibers was evaluated by field emission scanning electron microscopy (FESEM) and their topography was analysed by means of atomic force microscopy (AFM). MKS/PVA nanofibers were obtained with a diameter range from 0.146 to 0.315 μm, with a “smooth fiber concentration threshold” of 3 wt%, while MKS/PVP, fibers with diameters from 0.080 to 0.339 μm were produced, but 5 wt% MKS concentration fibers were beaded fibers, as a result of an excess in starch concentration. Finally, the roughness of the optimal fibers showed quite a similar trend to that of fiber diameter, presenting roughnessess between 80 and 343 nm.