Preparation and characterization of glycerol plasticized yam starch-based films reinforced with titanium dioxide nanofiller

In this study, yam starch was extracted from yam tubers using water and used for preparation of glycerol plasticized and titanium dioxide (TiO2) nanofiller reinforced films. The effects of TiO2 nanofiller concentration on the properties of the film were studied. Concentration of TiO2 nanofiller affects the mechanical and morphological properties of the film. The tensile strength and percent elongation were modeled and optimized by a three-variable, three-level Box-Behnken Design (BBD) using Response Surface Methodology (RSM). An optimal tensile strength (4.68 MPa) and elongation percentage (32.96%) were observed with the model at starch (3.60 g), glycerol (1.40 mL) and TiO2 nanofiller concentration (0.35 g) for the reinforced starch film. The experimental tensile strength and elongation percentage at break were 4.45 MPa and 37.77%, respectively. This shows the model can reasonably predict the optimum tensile strength and elongation of the current biofilms. Moreover, the biodegradability and antimicrobial properties of biofilms prepared at optimum tensile strength and elongation percentage were conducted. About 29% of the initial weight of the film was decomposed in the soil in the first 15 days. Moreover, an E. Coli inhibition zone of 3.25 mm was observed for the TiO2 reinforced films.