Bio-Based Plastic Based on Ozonated Cassava Starch Produced by Extrusion

Green methods of modification, such as ozone, can bring new functionalities to starch. In this study, starch-based plastics were produced by extrusion, using cassava starch ozonated with a gas flow of 1 L min(-1) at a concentration of 41 mg O-3 L-1 resulting in doses of 78.9 and 145.3 mg O-3/g starch. Pre-mixes (starch, glycerol, and water) were processed in a co-rotating twin-screw extruder. The main results showed that ozonated sheet produced with the treatment of 78.9 mg O-3/g starch resulted in an increase in Young Modulus by 43% and a decrease in hydrophilicity by 37% in comparison to the native one. Conversely, treatment with 145.3 mg O-3/g starch did not increase the bio-based plastic mechanical properties or surface characteristics, showing a specific behavior tendency between ozonation and extrusion processes. The ozonation of starch showed to be an alternative for producing by extrusion bio-based plastics with enhanced properties, by selecting adequate processing conditions. [GRAPHICS]