3.3. Mechanical properties
Table 2 presents the tensile properties and hardness of
the raw OPA and LENR-coated OPA filled NR composites.
From the results shown, the tensile strength and elongation
at break increased when a very low OPA loading was
added, but tended to reduce beyond 1 phr loading of the
OPA. The same trend was observed for the LENR-coated
OPA filled NR composites. Furthermore, the LENR-coated
OPA filled NR composites showed a higher value than
that of the raw OPA at a similar filler loading. It is deduced
that the coating layer of LENR had a positive contribution
to better adhesion by wetting the OPA more effectively
and reducing the micro-void within the raw OPA and the
NR matrix. As already noted, the LENR was able to penetrate
into the porous structure of the OPA, whilst the