Civil Engineering Reference
In-Depth Information
250
notched
PP matrix
PP/KE (1 mm) 40wt%
PP/KE (10 mm) 40wt%
182.3
200
165.9
144.9
150
100
41.1
37.5
50
31.8
24.0
21.4
17.6
0
clay 0 wt%
clay 5 wt%
clay 10 wt%
unnotched
PP matrix
PP/KE (1 mm) 40wt%
PP/KE (10 mm) 40wt%
400
315.1
289.4
261.7
300
158.2
172.7
200
152.7
164.3
131.1
137.0
100
0
PP matrix
KE (10mm)
KE (1 mm)
Figure 7.8
Notched impact strength and unnotched impact strength of PP/KE/clay nanobiocomposites.
I. Na. Sim
et al.
than those of PP/KE (1 mm) nanobiocomposites. h is increase can be explained by the
i ber bridging ef ect and the capability improvement of the long i ber to absorb impact
energy which led to stop crack spread [31].
7.3.7
SEM and EDX Observation
h e fractured surfaces of nanobiocomposites were observed by SEM and EDX.
Figure 7.9 shows the scanning electron micrographs of the impact fractured surfaces
of PP/KE (10 or 1 mm) nanobiocomposites of 5 wt% nanoclay loading. h e fractured
surface of PP/KE (10 mm)/clay nanobiocomposites shows the cut-of phenomenon of
i bers, attributed to the ef ective stress transfer by long i bers in composites and good
interfacial adhesion between i bers and matrix, hence resulting in the improvement of
mechanical properties. Whereas the fractured surface PP/KE (1 mm)/clay nanobio-
composites shows the many holes by pull-out of i bers from the matrix because of poor
stress transfer by short i bers in composites and weak interfacial bonding. h is indi-
cates that the adhesion between i ber and matrix in PP/KE (10 mm)/clay nanobiocom-
posites is much more ef ective than that of the PP/KE (1 mm)/clay nanobiocomposites.
h e EDX analysis showed the elemental composition on the surface of the nano-
biocomposites. Figure 7.10 shows the energy dispersive X-ray spectroscopy mapping
image and spectrum of the fractured PP/KE (10 mm)/clay nanobiocomposites. h e
