92
4 PVA Bionanocomposite Films with Different Particle …
Fig. 4.5 Relative change of
surface roughness in terms of
filler content in PVA
bionanocomposites [12]
Notwithstanding that the same manufacturing process condition and nanofiller
contents have been utilised for preparing PVA bionanocomposite films, different
nanoparticle types play an important role in the variation of the degree of roughness. Overall, with increasing the nanofiller content, the surface roughness of PVA
bionanocomposites in this study was enhanced to different extent, as evidenced by
increasing the maximum relative change of surface roughness up to 589.4, 218.4 and
115.8% with the inclusion of HNTs, Cloisite 30B clays and NBCs at the same filler
content of 10 wt% shown in Fig. 4.5. Such a phenomenon suggested that NBCs might
have better ability to be dispersed more uniformly in PVA matrices, as opposed to
HNTs and Cloisite 30B clays due to their least increasing level in surface roughness
especially when beyond 5 wt% in filler content.
While the effect of different nanoparticle shapes and sizes on surface roughness
of PVA bionanocomposites became less pronounced at low filler contents below 3
wt%.
4.6 Aspect Ratios of Embedded Nanofillers in PVA
Bionanocomposites
The aspect ratio of nanofillers is regarded as one of key factors in reinforcement efficiency and mechanical performance of nanocomposites, which is generally defined
as the ratio between the largest dimensions over the smallest dimension of nanofillers.
According to this fundamental concept, the largest dimension of nanofillers can be
represented by the lengths of tubular HNTs and platelet-like Cloisite 30B clays or
the diameters of NBCs while the smallest dimension denotes the diameter of HNTs
or thicknesses of Cloisite 30B clays and NBCs [23].
4 PVA Bionanocomposite Films with Different Particle …
Fig. 4.5 Relative change of
surface roughness in terms of
filler content in PVA
bionanocomposites [12]
Notwithstanding that the same manufacturing process condition and nanofiller
contents have been utilised for preparing PVA bionanocomposite films, different
nanoparticle types play an important role in the variation of the degree of roughness. Overall, with increasing the nanofiller content, the surface roughness of PVA
bionanocomposites in this study was enhanced to different extent, as evidenced by
increasing the maximum relative change of surface roughness up to 589.4, 218.4 and
115.8% with the inclusion of HNTs, Cloisite 30B clays and NBCs at the same filler
content of 10 wt% shown in Fig. 4.5. Such a phenomenon suggested that NBCs might
have better ability to be dispersed more uniformly in PVA matrices, as opposed to
HNTs and Cloisite 30B clays due to their least increasing level in surface roughness
especially when beyond 5 wt% in filler content.
While the effect of different nanoparticle shapes and sizes on surface roughness
of PVA bionanocomposites became less pronounced at low filler contents below 3
wt%.
4.6 Aspect Ratios of Embedded Nanofillers in PVA
Bionanocomposites
The aspect ratio of nanofillers is regarded as one of key factors in reinforcement efficiency and mechanical performance of nanocomposites, which is generally defined
as the ratio between the largest dimensions over the smallest dimension of nanofillers.
According to this fundamental concept, the largest dimension of nanofillers can be
represented by the lengths of tubular HNTs and platelet-like Cloisite 30B clays or
the diameters of NBCs while the smallest dimension denotes the diameter of HNTs
or thicknesses of Cloisite 30B clays and NBCs [23].