Bio-based composites of sago starch and natural rubber reinforced with nanoclays
Jareerat Ruamcharoen
, Ruszana Munlee, Lapporn Vayachuta, Polphat Ruamcharoen
, Ruszana Munlee, Lapporn Vayachuta, Polphat RuamcharoenVol. 17., No.11., Pages 1096-1109, 2023
DOI: 10.3144/expresspolymlett.2023.83
DOI: 10.3144/expresspolymlett.2023.83
Corresponding author: Jareerat Ruamcharoen 
GRAPHICAL ABSTRACT
ABSTRACT
Sago
starch (SS) was blended with natural rubber (NR) using nanoclays, namely
montmorillonite (MMT), kaolinite (KAO), and kaolinite modified by dimethyl
sulfoxide (KAO-D) to enhance its physical and mechanical properties. Each nanoclay
was incorporated at 2, 4, 6, and 8 wt%, respectively. The SS80NR20 (80 wt% of
sago starch and 20 wt% of natural rubber) biocomposites were characterized by
solubility of water, water vapor transmission, mechanical and thermal
properties. The constituent interaction and morphology of the SS80NR20
biocomposites were also presented by using X-ray diffraction (XRD) technique
and scanning electron microscope (SEM). The findings demonstrated that the
inclusion of clays significantly improved both the water resistance and tensile
properties when compared to the SS80NR20 blend. In the SS80NR20 biocomposites,
MMT at 6 wt% exhibited the lowest moisture content, solubility in water, and
water vapor transmission. As the amount of nanoclay in the biocomposites
increased, their tensile strength dramatically increased whilst their strain at
break had a tendency to diminish. Strong interaction by establishing the
intercalated structure of MMT, and KAO within SS80NR20 biocomposites were
attributed to both physical and mechanical properties, while the weak
interaction at the interface of SS and NR was attributed to KAO-D.
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