Preparation and Characterization of Starch/Polyvinyl Alcohol Blend Films by the Application of Gamma Radiation

摘要

Biodegradable films were prepared from the blend of starch/polyvinyl alcohol (PVA) with 4% (w/w) chitosan of total polymers (starch and PVA) by casting method. The effect of starch/PVA composition (starch/PVA = 30/70, 40/60, 50/50, 60/40) on tensile properties was investigated. It was found that both tensile strength and elongation at break decreased with increased amount of starch in the starch/PVA blend. The starch/PVA composition, starch/PVA = 40/60 was optimized with respect to tensile strength. The effect of radiation dose (0-50 kGy) on tensile properties of prepared film was studied. Tensile strength increased while elongation at break decreased with increase in radiation dose. The highest tensile strength of -30 MPa was obtained for 25 kGy radiation dose which is 68% higher than non-irradiated starch/PVA blend film. The thermal property of the non-irradiated and irradiated film was investigated using thermos-gravimetric analyzer and dynamic mechanical analyzer. The structural feature of blend film was investigated using FTIR. The application of blend film as wrapping material on guava showed that the weight loss of wrapped guava was lower than that of control guava.