DSC curves of CSCS, PVA, SF nanoparticle and the CECS/PVA/SF
nanofibers are reported in Fig. 5. For SF nanoparticle (Fig. 5d), there
displayed one wide endothermic peaks centered at about 142 ◦C,
which could be attributed to the water lost during the DSC run.
In addition, a clear glass transition was detected at about 125 ◦C,
lower than the value reported in the literature (174–177 ◦C) [30],
which was possibly due to plasticization effect of their moisture
that plasticized the amorphous phase [31]. The pure PVA powder
showed a relatively large and sharp endothermic curve with a peak
at 193 ◦C. However, the endothermic curve of SF/CECS/PVA blend
fibers became obtuse and broad, and the peak shifted toward higher
temperatures. This indicated that the crystalline microstructure
of electrospun fibers did not develop well, which was because
the majority of the chains were in the noncrystalline state due to
the rapid solidification process of stretched chains during electrospinning.