Effect of Different Molecular Weight of PEG on the Crystallization Behaviors of Binary Polymer Blends PLA/TPS

Abstract

Serial poly (lactic acid) (PLA) and thermoplastic starch (TPS) blends (with a fixed content of 20 wt.% TPS) were prepared by melt extrusion process. The effect of different molecular weight of PEG on the thermal and rheological properties of PLA/TPS blends was studied by the melt flow rate (MFR) and DSC analysis. The results showed that the molecular weight of PEG influenced the miscibility and crystallization behavior of PLA/TPS blends. Blend added with PEG400 showed a single Tg, and blends with PEG600 provided remarkable improvement of rheological properties with an increase in flow rate to 49.02 g/10 min. 4% content of poly (ethylene glycol) (PEG) can positively contribute to improve crystallization rate of PLA by reducing the melting temperature and cold crystallization temperature.