In-situ Raman spectroscopy monitoring of the thermal and oxidative accelerated degradation of poly(L-lactide) (PLLA) and poly(lactide-co-glycolide) (PLGA) polymers

The purpose of this study is to investigate the change in chemical structures of biopolymers PLGA 80:20 and PLLA during thermal and oxidative degradation by the means of in-situ Raman spectroscopy monitoring. Both isothermal and non-isothermal testing, with or with little presence of oxygen, will be conducted to monitor the changes in chemical configuration of biopolymers with respect to the increasing degradation temperature or time. It was found that the number of carbonyl groups and vas CH3 and vCH stretching regions decreased with increasing degradation. The former was due to degradation of carbonyl group while the latter was due to random chain scission. The COC regions (1092 v/cm-1, 1179 v/cm-1 and 1216 v/cm-1) were very stable throughout the whole degradation process. Interestingly, the CCO region (398 v/cm-1 to 441 v/cm-1) increased with prolonged degradation time. This was due to the increase in degree of crystallinilty (DOC) of the biopolymers. This increase could be further confirmed by the analysis done by TGA.Bachelor of Engineering (Materials Engineering