Civil Engineering Reference
In-Depth Information
of nanocellulose before and at er their production process. In this test, dried and pow-
dered form samples are blended with KBr and then compressed. h e spectra of samples
are recorded in the range of 4000 to 400 cm−1 [63]. For example, the FTIR spectra of
NFC from cotton linter can be seen in Figure 11.13 and its peak analysis is summarized
in Table 11.2 [47].
11.4.2
h
ermal Properties
h ermal decomposition properties of nanocellulose are determined by thermogravi-
metric analysis (TGA). In general, around 5 mg of sample is placed in a platinum pan
and heated with rate of 10°C/min from 20 to 600
°
C [137] . Figure 11.14a shows the TGA
curves of CNC from jute i ber [137]. As the authors mentioned, the degradation of
untreated jute i ber, alkali-treated i ber and TEMPO-oxidized CNC started at 270, 270
and 200°C, respectively. h ey described that TEMPO oxidation causes a reduction in
thermal degradation due to generation of sodium carboxylate groups. Figure 11.14b
0.8
Abs
0.6
After 30 passes
0.4
0.2
Control ibre
0
4000
3500
3000
2500
2000
1500
1000
500
1/cm
Wavenumber (cm
-1
)
Figure 11.13
FTIR spectra of NFC from cotton linter [47].
Table 11.2
FTIR peak a
nalysis of NFC from cotton linter [47].
Peak (cm
-1
)
Assigning to
NFC from cotton
i ber
4000-3000
hydrogen-bonded OH stretching
2900
CH stretching
1635
OH bending of adsorbed water
1429
HCH and OCH bending vibrations
1371
CH deformation vibration
1265
-C-O-C- bond
900
COC, CCO, and CCH deformation and stretching
vibrations
