the fractured surfaces of STR 5L, ENR-25 and SBR compounds with 10 phr
(Fig. 11a–c) and 40 phr (Fig. 11d–f) chitosan taken at
magnification of 150-x. With increasing chitosan loading,
the fractured surfaces show poor dispersion and adhesion
of chitosan to STR 5L, ENR-25 and SBR (Fig. 11a–c), whereby
there were agglomerations and significant detachment of
chitosan from the filled compound. Greater detachment (as
circled) can be seen in the rubber compounds with 40 phr
chitosan (Fig. 11d–f). The formation of holes indicates that
the resulting chitosan detachments have contributed to the
reduction in tensile strength with increasing chitosan
loading. However, at a similar loading, the SEM micrographs
show that more significant detachment occurs in
SBR compounds as a result of the poor interaction between
the chitosan and rubber which contributes to the lower
strength of these compounds.