Mechanical and degradation properties in alkaline solution of poly(ethylene carbonate)/poly(lactic acid) blends

Thin films of PEC/PLA blend exhibiting improved toughness and biodegradability in alkaline solutions were prepared by a simple solution casting method. With the addition of 50 wt% PEC, the toughness of PEC/PLA blend was improved to a peak value of 45.8 MJ/m3, in contrast to 6.7 MJ/m3 for neat PLA. Young's modulus of PEC/PLA blends at low PEC ratio were fairly similar to that of neat PLA. Addition of more than 40 wt% of PEC enhanced the biodegradability of PLA in alkaline solution. The weight loss of hydrolysed PEC/PLA blends changed non-linearly with the addition of PEC, and depended strongly on PLA crystallinity and the ratio of PEC to PLA. This enhancement was attributed to the high toughness and degradability of PEC/PLA blends induced by partial miscibility, as reported previously.