The torque of pure PBS and PBS/nano-CaCO3 composites
as a function of frequency at 150 C is shown in Fig. 8. It can
be seen that the torque increased with an increase of the
frequency, which reflects the viscosity change with frequency.
Compared to pure PBS, the torque of PBS/nanoCaCO3
composites was increased significantly, and this effect
was enlarged with an increase in nano-CaCO3 content
when the frequency exceeded 10 rad/s. This phenomenon
is due to the increased viscosity of the PBS/nano-CaCO3
composites with increasing nano-CaCO3 content.