Radiation crosslinking of biodegradable poly(butylene succinate) at high temperature

Poly(butylene succinate), (PBS) with different molecular weight was gamma - irradiated at different temperatures and various doses. PBS with high molec ular weight and smaller peak area of crystal melting gave the highest gel c ontent at the same temperatures and dose. A two-step irradiation (irradiati on in molten state after irradiation at room temperature) gave the highest gel content in different conditions. This is due to the formation of networ k structure by pre-irradiation at room temperature that leads to less degra dation. PBS prepared by two step irradiation was effective for improvement of heat stability because of high gel content formation. Unirradiated PBS s heets broke immediately at 110 degrees, while the irradiated sample (gel fr action, 50%) by a two step-method did not break even up to 200 minutes at 1 30 degreesC. The PBS sheets are biodegradable even after crosslinking.