The morphology of the core, seen in Fig. 3b, consists of spherical
domains of 1.5 mm diameter. The outer layer is not discussed
here since it was very thin (about 100e150 mm). As
a consequence of its thinness, it would have negligible influence
on the mechanical properties. Only the morphological
data of the inner part of the specimens are considered in this
study. Fig. 4 shows the SEM micrographs of various blends’
ratio of PET/NR. The particle sizes of the rubber in the blends
and its impact strength are plotted with the blend composition
as shown in Fig. 5. It