Creating novel materials at scale of nano with advanced applications has been attracted by the scientists during the past two decades. Electrospinning is one straightforward method of the nanotechnology which has impacted many different sciences and engineering disciplines such as materials science and polymer engineering [1]. Electrospinning is used to process (mainly polymers) solutions or melts into the continuous fibres with diameters ranging from micrometers to nanometers (100 nm). By using a high voltage electric field the polymer solution or melts can be charged electrically and by evaporation of the solvent dried nanofibres can be produced. The highly charged fibres are field directed towards the negative/neutral charged collector, which can be a flat surface or a rotating drum, to collect the fibres [1]. There are some in-depth reviews of research activities on the development of electrospinning process, properties of nanofibres and their applications have been provided. Nanofibres with diameters below 100 nm have smaller pores and higher surface area than regular fibres, can be used in enormous applications in nanocatalysis, tissue scaffolds, separation membranes, wound-dressing materials, artificial blood vessels, filter medium, adsorption layers in protective clothing, filtration and optical electronics [1-3].
In order to generate superabsorbent nanofibres with capability of absorbing and retaining of water with respect to maintain of their mechanical integrity and strength, superabsorbent polymers and other ingredients (like elastomers) were mixed and then prepared by electrospinning machine [3,4]. In the present work the electrospinning of various superabsorbent poly (acrylic acid) (PAA) and polyvinyl alcohol (PVA) solutions with different concentration in the solvent were prepared. We investigated the effect of governing parameters, on the thickness and size of nanofibres. Figure shows scanning electron microscopy (SEM) results of superabsorbent nanofibre of PAA and PVA.
In future work we will mainly focus on characterise these nanofibres and make them as the internal water channels in hydrophobic materials for superabsorbent nanocomposites.
Figure: SEM images of hydrogel nanofibres with 20 wt% PAA (left) and 10 wt% PVA (right) diluted in DI water.
Article written by Nazila Dehbari, Supervisor Dr Youhong Tang
References
[1] Subbiah, T., Bhat, G. S., Tock, R. W., Parameswaran, S., Ramkumar, S. S. (2005) Electrospinning of nanofibers. J. Appl. Polym. Sci., 96: 557-569.
[2] Doshi, J., Reneker, D. H. (1995) Electrospinning process and applications of electrospun fibers. J. Electrostat., 35: 151-160.
[3] Hansen, L. M., Smith, D. J., Reneker, D. H., Kataphinan, W. (2005) Water absorption and mechanical properties of electrospun structured hydrogels. J. Appl. Polym. Sci., 95: 427-434.
[4] Tang, C., Ye, S., Liu, H. (2007) Electrospinning of poly(styrene-co-maleic anhydride) (SMA) and waterswelling behavior of crosslinked/hydrolyzed SMA hydrogel nanofibers. Polymer, 48: 4482-4491.