PBS is widely known as a semicrystalline polymer; its physical,
mechanical and thermal properties are relied on crystallinity [30].
To confirm these relationships, the thermal behavior of the PBS/
ZnO composite films at the second heating scan was determined
by DSC and graphically presented in Fig. 5. Their corresponding
transition temperatures, area under peaks and Xc were summarized
in Table 3. In Fig. 5(a), the melting endotherms of neat PBS
and its composites had similar characteristic. Their melting points
were almost the same. Cooling thermograms in Fig. 5(b) indicated
that PBS crystallized earlier with reductions of the crystallization
temperature (Tc) by around 3–9 C up to ZnO content. It was
observed from Table 3 that Tc decreased by 3 C when ZnO reached
2 wt%. Beyond this concentration, Tc achieved the minimum value
at 79.1 C when ZnO was added at 8 wt%. As summarized in Table 3,
Xc of PBS composites were slightly increased after ZnO incorporation.
In this case, the increased PBS crystallinity partially induced
an improvement of the tensile strength while a significant reinforcement
of the strength and modulus mostly contributed by
the dispersed ZnO particles. In PP, DSC measurements showed that
adding ZnO led to the increased Xc [12]. However, adding ZnO rodlike
nanoparticles to PLA was found to increase the amorphous
region