The flexural strength and modulus of the composites are shown
in Fig. 1b as functions of the coupling agent and nanoparticle
contents. The flexural properties of the composites vary significantly
with MWCNTs and MAPE contents (Table 4). Similar with the
trend results of tensile properties, composites made with 1.5 wt%
MWCNTs and 4 wt% MAPE showed the maximum strength and
modulus of flexural, whereas composites without MWCNTs and
MAPE exhibited the lowest properties.