| 초록 |
Polylactide (PLA) exhibits good thermal and mechanical properties. Therefore, PLA has been widely used for packaging films, fibers, and engineered thermoplastics. In the previous study, we investigated the physical aging behavior of the PLA with different D-isomer content as a function of temperature and time by using DSC. As the result, we found that the changes of Tg and relaxation enthalpies of PLA with aging temperature and time were dependent on the D-isomer content in PLA backbones. We expect that the different physical aging behavior of PLA stems from the difference in the segmental motion of PLA backbones. To obtain a further deep understanding on the correlation among physical aging, properties and molecular mobility of PLA, in this study, the conformation energy calculation and the oxygen gas transmission rate measurement for PLA with various D-isomer contents were carried out by the molecular modeling technique and the equal pressure method, respectively. |
