Abstract:
Water hyacinth (Eichhornia crassipes) is an
invasive aquatic plant widely distributed in freshwater
bodies in Sri Lanka. Its rapid proliferation obstructs
waterways and adversely affects aquatic ecosystems. This
biomass is often removed during management activities,
but its productive use is limited, presenting an
opportunity to turn this resource into a value-added
material. This study investigated the valorization of E.
crassipes biomass for the development of biodegradable
starch-based sheets intended for food-packaging
applications. The collected biomass was subjected to
sodium bicarbonate (NaHCO3)-assisted alkaline boiling,
pulped, and incorporated into a cassava-starch matrix.
Three water hyacinth fibre/starch formulations, 40:60
(S1), 50:50 (S2), and 60:40 (S3), were fabricated by wet
forming and evaluated for tensile strength, density, water
absorption, and thickness. The fibre/starch ratio
considerably influenced the measured properties. S2
achieved the highest tensile strength of 63.73 MPa,
whereas S1 and S3 recorded 54.80 and 58.00 MPa,
respectively. S1 exhibited the lowest density (0.83 g/cm3),
water absorption (141.66%), and thickness (2.0 mm),
compared with 1.08 g/cm3, 170.00%, and 2.6 mm,
respectively, for S3. The 40:60 fibre/starch formulation
showed the best overall performance, though its high
water absorption indicates a need for better moisture
resistance. These findings suggest a method to transform
invasive E. crassipes biomass into biodegradable
packaging, connecting aquatic weed management with
waste valorization material use in Sri Lanka.
