Effect of various γ-ray dose on the microstructure and properties of poly(lactic acid)

• Main Authors: Kuo-Hsiung Wang, 王國雄
• Other Authors: Tzong-Ming Wu
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/91937315858074503007

碩士 === 國立中興大學 === 材料科學與工程學系 === 96 === Polylactic acid (PLA), a well-known biodegradable and biocompatible polymer, contain excellent mechanical and thermal properties. Among these biodegradable polymers, PLA provides a possible candidate to replace the traditional plastics in the applications of packaging materials, bio-materials and fibers. Different procedures can be utilized for the sterilization of the food and medical instruments. Gamma irradiation used for sterilization has performed excellent penertration characteristics of ionizing radiation and high efficient sterilization. The purpose of this study is to examine the effect of dose for gamma radiation on the microstructure and properties of PLA. The glass transition, melting temperatures and molecular weight decreased with increasing irradiation dose. The mechanical property and thermal stability for PLA thermally treated before irradiation are higher than those treated after irradiation or without annealing treatment. The in situ X-ray diffraction studies have shown that the treatment of gamma irradiation decreases the recrystallization temperature.