MOISTURE UPTAKE AND TENSILE PROPERTIES OF STARCH-SUGAR CANE FIBRE FILMS
By WN GILFILLAN; PA SOPADE; WOS DOHERTY
THERE IS AN increasing need for biodegradable plastics because they are
environmentally friendly and can replace petroleum-based non-degradable plastics
which pollute the environment. Starch-derived films reinforced with sugar cane bagasse
fibre, which are biodegradable, have been prepared and characterised by gravimetric
analysis for moisture uptake, X-ray powder diffraction for crystallinity, and tensile
testing for mechanical properties. Results have shown that the addition of bagasse fibre
(5 wt%, 10 wt% or 20 wt%) to either (modified) potato starch (Soluble starch) or
hydroxypropylated maize starch reduced moisture uptake by up to 30% at 58% relative
humidity (RH). Also, the tensile strength and the Young’s Modulus increased up to 63%
and 80% respectively, with the maximum value obtained with 5 wt% fibre at 58% RH.
However, the tensile strain of the films significantly decreased by up to 84%. The
results have been explained based on the crystallinity of the films and the intrinsic
properties of starch and bagasse fibres.