1.4 Nanofillers for Bionanocomposites
15
bonding to create filler networks within polymer matrices [108]. It has been reported
that HNT/MEL-based nanocomposites possess an increased flexural modulus of
3.65 GPa and flexural strength of 109.1 MPa when compared with those of unfilled
polymer (1.93 GPa and 79.7 MPa, respectively) [109].
1.4.3 Bamboo Charcoals (BCs)
Bamboos, as naturally grown plants, are usually discovered in East Asia, but currently
grow worldwide, especially in subtropical regions [110]. Moreover, bamboo forests
cover approximately 22 million hectares, which is equivalent to 1% of total global
forest areas [110]. Bamboos are also considered as inexpensive and ecofriendly
materials without the required fertilisers, or pesticides for their growth. Bamboos
can be converted into widely used charcoals with typical porous structures when
carbonised or pyrolysed. The carbonisation is carried out at inert atmosphere and
temperature above 700 °C when bamboos start to release the water content and
organic gases, which is followed by the reconstruction of carbon structures [111].
Although the volume of bamboo can shrink significantly during the carbonisation,
their tubular structures still well remain. Figure 1.9 presents morphological structures
for the cross-sectional and lateral views of BCs carbonised at 1000 °C, which confirms
apparent porous nature of original bamboos [110].
In previous work [112], the morphological structures and shrinkage of BCs were
investigated at different carbonisation temperatures, which showed that the scaffolding of BCs was similar to that of original bamboos despite a slight change of
bamboo microstructures during the shrinkage. Furthermore, the shrinkage ratios of
bamboo carbonised at 500, 750 and 1000 °C were found to be about 21, 38 and
40%, respectively. Furthermore, morphological structures of bamboo charcoals under
Fig. 1.9 Scanning electron micrograph of raw bamboo biotemplate after pyrolysis: a cross-sectional
view and b lateral view [110]
15
bonding to create filler networks within polymer matrices [108]. It has been reported
that HNT/MEL-based nanocomposites possess an increased flexural modulus of
3.65 GPa and flexural strength of 109.1 MPa when compared with those of unfilled
polymer (1.93 GPa and 79.7 MPa, respectively) [109].
1.4.3 Bamboo Charcoals (BCs)
Bamboos, as naturally grown plants, are usually discovered in East Asia, but currently
grow worldwide, especially in subtropical regions [110]. Moreover, bamboo forests
cover approximately 22 million hectares, which is equivalent to 1% of total global
forest areas [110]. Bamboos are also considered as inexpensive and ecofriendly
materials without the required fertilisers, or pesticides for their growth. Bamboos
can be converted into widely used charcoals with typical porous structures when
carbonised or pyrolysed. The carbonisation is carried out at inert atmosphere and
temperature above 700 °C when bamboos start to release the water content and
organic gases, which is followed by the reconstruction of carbon structures [111].
Although the volume of bamboo can shrink significantly during the carbonisation,
their tubular structures still well remain. Figure 1.9 presents morphological structures
for the cross-sectional and lateral views of BCs carbonised at 1000 °C, which confirms
apparent porous nature of original bamboos [110].
In previous work [112], the morphological structures and shrinkage of BCs were
investigated at different carbonisation temperatures, which showed that the scaffolding of BCs was similar to that of original bamboos despite a slight change of
bamboo microstructures during the shrinkage. Furthermore, the shrinkage ratios of
bamboo carbonised at 500, 750 and 1000 °C were found to be about 21, 38 and
40%, respectively. Furthermore, morphological structures of bamboo charcoals under
Fig. 1.9 Scanning electron micrograph of raw bamboo biotemplate after pyrolysis: a cross-sectional
view and b lateral view [110]