Production of biodegradable plastic films using starch extracted from cassava tubers modified with natural clay

In this study, biodegradable plastic films were produced using starch extracted from cassava tubers via a wet milling process. The films were developed using casting techniques, and their properties were enhanced by the incorporation of natural clay. The proximate composition of the starch, including dry matter content, starch yield, moisture content, pH, ash content, protein, amylose, and amylopectin, was analyzed using standard methods and fell within the industry-recommended ranges. The thermal stability, morphology, and structural properties of the extracted starch and films were examined using TGA, DSC, SEM, FTIR, and XRD. TGA results indicated thermal stability up to 248°C, while DSC analysis showed onset, peak, and end temperatures of 68, 150, and 185°C, respectively, with a melting enthalpy of 15 J/g. As the clay percentage increased from 1 to 9 %, the films' thickness, density, ash content, and thermal characteristics all increased, while their moisture content and water absorption decreased. FTIR confirmed the effective interaction between clay and the starch matrix, while XRD revealed the intensity of the Si-O-Si bands with higher clay loading. These findings highlight the potential of cassava starch-based bioplastics reinforced with natural clay for sustainable food packaging, which offers improved thermal and barrier properties.   Key words: Starch, clay, composite, glycerol, biodegradable film, casting.