The Optimized Electrospun Poly (Lactic Acid)/MWCNTs Fibrous Nanocomposites: Electrical Measurements and Morphological Studies

The prospect of this work was to probe the morphology and electrical properties of optimized poly (lactic acid) (PLA) nanofibers containing multi-walled carbon nanotubes (MWCNTs). In order to attain the appropriate sample, the effective parameters such as polymer solution concentration, MWCNTs content, flow rate, solvent ratio (trifluoroacetic acid (TFA)/dichloromethane (DCM)), applied voltage and syringe needle tip-collector distance have been optimized via D-optimal design method. The optimum amounts of parameters in the order of above mentioned were 5%(v/w), 1.05 mg, 0.6 mL/h, 8.5:1.5, 16 kV and 16.5 cm. Optimization of these variables caused to obtain conductive along with suitable morphology for a PLA-based fibrous nanocomposite sample. The influence of changing the effective parameters were investigated by scanning electron microscopy (SEM) and conductometry tests which resulted in a minimum mean diameter (~80 nm) and a maximum electrical conduction (~1.8×10-5 S/cm) in the sample. These results were also confirmed by contour length curves obtained from response surface methodology.

Keywords:

poly (lactic acid) , carbon nanotubes , nanofibers , morphology , electrical properties