To prepare the NiO-PBT nanocomposite, 0.14 g of PBT (14% w/v)
was initially dissolved in 1mL of TFA and stirred for 10 min to
obtain a homogenous solution. Then, various amounts of NiO
nanoparticles were added into the polymeric solution and it was
vigorously stirred for 10 min (1000 rpm) to obtain a homogenous
solution. Then 0.5mL of this solution was withdrawn into a 1mL
syringe which was eventually located in a syringe pump. A
homemade SPME devicewas attached to a small electrical motor in
away that the plunger wire could be rotated while electrospinning
was performed. Under this condition, the external needle and the
polymer containing syringe needle were connected to the high
voltage power supply terminals. A length of 1.5 cm from the end
part of plunger wire was used to collect the nanofibers. The other
part of the SPME assembly was protected from the nanofibers
flying toward the collector by a packed paper insulator. The
distance between the needle and the collector was set at 10 cm.
The SPME assembly was in orthogonal position in respect to the
syringe. A voltage of 16 kV was applied for the nanofibers
production while a flow rate of 0.5mLh1 was set for the polymer
solution delivery using a syringe pump. All the electrospinning
processes were performed under the ventilation (Fig.1a). All fibers
were electrospun for 2 min. Finally, the SPME fibers were inserted
into the GC injector port for conditioning at 240 C for 3 h.