Gamma-ray irradiation is a very useful tool to improve the physicochemical properties of various biodegradable polymers without the heating and cross-linking agent. The purpose of this study was to investigate the degradation behavior of polyester polymers depending on the gamma-ray irradiation. Polymer films prepared by a solvent casting method were irradiated with gamma radiation at various irradiation doses. The irradiation was performed using by 60Co gamma-ray doses of 0, 25, 50, 100, 200 and 500 kGy at a dose rate of 10 kGy/hr.
The degradation of irradiated films was observed through the chain scission and peroxidation. Exposure to gamma radiation dropped the value of average molecular weight (Mn and Mw), and weaken mechanical strength. Thermograms of after irradiated film show various changes of thermal properties in accordance with gamma-ray irradiation dose. Gamma-ray irradiation changes morphology of surface, and improves the wettability. In conclusion, the gamma-ray irradiation will be a useful tool to control the rate of hydrolytic degradation of these biopolymers.