| Abstract: | Poly(-caprolactone), PCL, (melting temperature, 60°C) was gamma-irradiated in the solid state at 30–55°C, the molten state, and the supercooled state (irradiation at 45–55°C after melting, 80°C) under vacuum to improve its heat resistance. Irradiation of PCL in the supercooled state led to the highest gel content and this polymer has high heat resistance. On the other hand, relatively smaller doses such as 15 and 30 kGy were effective to improve processability of PCL by formation of branch structure during irradiation. |
