Fabrication of Chitosan Nanofibers Membrane with Improved Stability and Britility
Haider, Sajjad . 2012
In the present work, we undertake the preparation of chitosan nanofibers via electrospinning by varying solution concentration (1, 2, 3, 4 and 6 wt% (w/v)), applied voltage (14, 18 and 22 kV), flow rate (0.4 mL/h and 0.8 mL/h), needle diameter (0.2 mm and 0.8 mm) and distance between needle tip and collector (100 mm and 140 mm). No electrospinning was observed for 1–3 wt% samples, where as improved physical texture, decrease in the number and size of microspheres and beads (in case of 4 wt%), and beads free nanofibers were obtained when the concentration of solution was changed from 4 to 6 wt%, applied voltage and needle diameter from 14 kV, 0.2 mm to 22 kV and 0.8 mm, respectively. The optimized conditions (i.e., 6 wt%, 22 kV, 0.4 mL/h, 0.8 mm) were used to produce nanofibers sheets/membranes. The membranes were stabilized in aqueous solution by treating those with anhydrous potassium carbonate (K2CO3) and glutaraldehyde ((C5H8O2) GTA vapors) individually, and the combination of both. The samples produced with the combination of both methods showed no dimensional shrinkage (as shown by neutralized samples), morphological degradation and enhanced aqueous (i.e., 94% weight remained) and thermal (i.e., degradation temperature is the range of 190–333 °C and the weight loss was 48%) stabilities.
We prepared multi-walled carbon nanotube (MWNT)/gelatin composites by dispersion of MWNT through ultrasonication in an aqueous medium with anionic surfactant sodium dodecyl sulfate (SDS).