Nylon 6, Nylon 6.6, PEO/water, PEO/water/Ethanol, PVA/FeCl3 and PEO/wood pulp have been successfully electrospun into nanofibres in the range of 200 nm to 1500 nm.
A comprehensive understanding of the effect of processing parameters on the morphological structure of these nanofibres has been established. Parameters such as
concentration of polymer solution, applied voltage, electrospinning collection distance
and flow rate have been found to affect fibre morphology. For Nylon 6 and Nylon 6.6
uniform nanofibres were produced using polymer solution concentrations, 20 wt.% and
25 wt.%, applied voltage of 15 kV, spinning distance of 8 cm and volume feed rate of
0.20 ml/hr. The produced nanofibres average diameter was 924 nm and 827 nm. For
PEO/water, PEO/water/Ethanol and PEO/wood pulp optimum conditions of polymer
solution concentration of 14 wt.% and 10 wt.%, an applied voltage of 15 kV, spinning
collection distance of 11cm and volume feed rate of 0.20 ml/hr and 0.25 ml/hr,
produced uniform nanofibres. The produced nanofibres average diameter was 452 nm,
544 nm and 494 nm. As for PVA/FeCl3, optimum conditions of polymer solution
concentration of 8 wt.%, an applied voltage 15 kV, spinning collection distance 11 cm
and flow rate 0.25 ml/hr produced uniform magnetic nanofibres. The produced
nanofibres average diameters were 789 nm. These parameters have consequently been
optimized to obtain uniform quality at different ranges of nanofibres. In this context it was established that the processing parameters vary significantly from one polymer to another but in general, the concentration the most important role in obtaining uniform fibre diameter without thin and thick places and beads. Applied voltage also played a significant role in determining the diameter of nanofibres and little significant effect on the fibre morphology was observed with the variation of spinning collection distance
and noticeable structural change with a change in the solution flow rate.
A selective range of microscopic techniques such as, Scanning Electron Microscopy,
Atomic Force Microscopy and Transmission Electron Microscopy were used to
characterise and evaluate the nanofibres produced during this study. DSC, X-ray
diffraction and FTIR was used to identify the thermal properties of Nylon 6.6, PEO and
PEO/wood pulp nanofibres produced.
Nanofibres produced in this study have a wide range of potential applications in
different fields, including, biomedical, magnetic sensor, mats for composite protective clothing, filtration, aerospace and others
