Helical twisting of electrospun liquid crystalline cellulose micro- and nanofibers

The first observation of a new conformational effect of helical twisting taking place during the electrospinning of cellulose was reported. the required amount of acetoxypropyl cellulose (APC) was weighed and dissolved completely in DMAc to give an iridescent lyotropic solution, characteristic of cholesteric mesophase. The solution was poured into a 5 mL syringe fitted with a 23-gauge needle, which was then placed on the infusion syringe pump (KDS100) to control the polymer solution feed rate. A D3100 with a Nanoscope IIIa controller was used for the AFM measurements, carried out in tapping mode under ambient conditions with the use of a commercial tapping-mode etched silicon probe. The results are interpreted with the help of a simple theoretical model for the tertiary structure of a chiral semiflexible filament, which is shown to wind into a helix along the axis of an external electric field.