Characterization of Low-Molecular-Weight PLA using HPLC

HPLC is applied and assessed as an effective tool to investigate both the production of PLA by polycondensation and its corresponding degradation. A new HPLC calibration procedure, through which it is possible to fully characterize LMW PLA samples by determining the concentration of each individual oligomer, is developed. A comparison between HPLC, H-1 NMR spectroscopy and non-aqueous solution titration is also reported in order to confirm the reliability of the proposed method. Finally, the proposed analytical technique is applied to monitor the development of a polycondensation reaction performed at 150 degrees C and 133.3 mbar for 12 h.