Abstract:
Modified rise starch film could be formed at the weight ratio of water modified rice starch 10:1-16:1. Tensile strength, elongation, Youngs modulus and thickness decreased as starch concentration decreased. Elasticgel (modified tapioca starch) quantity didnt affect the Youngs modulus. Changing of tensile strength and elongation depended not only on elasticgel but also starch concentration. Tensile strength, elongation were decreased when increasing glycerol quantity while Youngs modulus and thickness were increased. Glycerol didnt show any significant effect on water vapor permeability and gas permeability in this experiment. Addition of stearic acid decreased tensile strength and elongation of the film while Youngs modulus and thickness were increased. Water vapor permeability increased when stearic acid was increased. Water vapor permeability of the modified rice starch film which was composited with elasticgel could be decreased by increasing stearic acid. Stearic acid didnt show any significant effect on water vapor permeability and gas permeability in this experiment. Oxygen permeability of modified rice starch film was less than oxygen permeability of polypropylene film at the 55% relative humidity. At the 68% relative humidity oxygen permeability of modified rice starch film was more than polypropylene film.