THERMAL, TRANSPARENCY AND WATER SENSITIVITY PROPERTIES OF BLEACHED, CROSS-LINKED CASSAVA STARCH FILM

Abstract

This work investigated a novel study of the effect of bleaching and cross-linking cassava starch film. Native cassava starch was bleached with hydrogen peroxide (H2O2), cross-linking was carried out with oxidized sucrose while glycerol was added to enhance the plasticity of the film. Operating temperature and time of 90 oC and 10 Minutes respectively with and addition of 0.5 ml of glycerol gave the best bleached, cross-linked cassava starch film. UV-visible spectrophotometer analysis revealed that the cassava starch film produced at the above reaction conditions retained 88.2 % of its transparency at 96 hours water immersion. The water solubility test shows that the film experienced 52.02 % weight loss after 96 hours immersion in water. The thermo-gravimetric analysis (TGA) shows a significant improvement on the thermal stability with Temperature peak (Tp) of 420.75 oC, compared to 374.13 oC Tp of the control sample (unbleached, uncross-linked) of the cassava starch film.