2.1. Extraction of cellulose
Cavendish banana pseudo stem was obtained shortly
after the fruit has been harvested from a plantation in
Central Java Province in Indonesia. The obtained pseudo
stem was cut into small pieces (1 cm) then dried at 70 8C
in a cabinet dryer (Heraeus Instruments). The dried
product was ground into powder to pass through a 20
mesh sieve. Then the cellulose powder was cooked in 8%
NaOH at ratio of cellulose to solvent 1:20 (w/v) for 3.5 h
at 100 8C, the obtained black slurry was filtrated and
washed using distilled water and bleached with 5%
NaOCl for 3 h at 30 8C. The bleached cellulose was
washed again using distilled water until the odor of
hypochlorite could no longer be detected, then dried at
60 8C in a cabinet dryer.