w/v) and polyethylene glycol (4 % w/v) in 4:1 formic acid:
acetic acid solvent mixture (GCP) was also used for fiber
deposition in the continuous mode.
The distances between collecting surfaces and spinning
axes, respective nozzles tips, were set to 19 cm and 11 cm
for all experiments, whereas the diameters of horizontal
tubes or spinnerets (Figures 2(b) and (c)) were regulated to
be of 2.54 cm. A constant air flow of 30L per second was
assured by an external air compressor, model Fini-Amico
25. The air flow circulation inside spinning chamber is also
influenced by centrifugal effect. The other technological
conditions and parameters applied during the modified
rotary-jet spinning of polymer micro- and nanofibers are
summarized in the Table 2.
Characterization
The morphological properties of polymer fibers obtained
through the current modified rotary-jet spinning process
were examined using a Vega-II Tescan scanning electron
microscope (SEM, Czech Republic), and Atlas Tescan software
for image analysis. Prior to SEM investigation, all samples
were sputtered with gold. An accelerating voltage of 30 kV
was used for image acquisition. The SEM images were
furthermore analyzed by using the ImageJ software (NIH,
USA) in order to have a better approximation of the fiber
thickness and their diameters distribution.
Results and Discussion
The rotary-jet spinning based on centrifugal effect represents
one of the most recent and efficient ways to obtain fibers
with diameters varies from tens of nanometers to a couple of
micrometers. Despite it’s already proved advantages over
other methods like electrospinning, the rotary-jet spinning
processes are susceptible to further modifications in order to
add even more improvements, one of such modification
being reported in the present work. Moreover, the use of