Isolation of Cellulose Nanowhiskers from Kenaf Fiber - Natural Polymers, Biopolymers, Biomaterials, and Their Composites, Blends, and IPNs - page 194

Figure 5. TEM image of cellulose nano whiskers kenaf fiber.
Xrd analysis
In order to analyze the crystallinity of the cellulose obtained in this work x-ray dif-
fractometry was carried out (Figure 6) . The crystallinity index was determined based
on the empirical method by using the following equation (Mwaikambo and Ansell,
2002; Segal et al., 1959).
C Ir(%) = (I 200 - I am ) / I 200 × 100
where I 200 is the peak intensity corresponding to the crystalline material and I am to the
amorphous material in cellulose fibers. Results show an increase in the crystallinity
from the raw kenaf fiber to the cellulose fiber which indicates the removal of hemicel-
luloses and lignin that have random amorphous structure (Rongji et al., 2009). The
pattern indicated that cellulose obtained from kenaf fiber presented a typical form of
cellulose I since there was no doublet in the main peak at 2θ=22.5° (Klemm et al.,
2005). The crystallinity index for raw kenaf fiber after alkali treatment, after bleach-
ing treatment and cellulose nanowhiskers were found to be 60.8%, 68.2%, 72.8%, and
81.8%, respectively.