Polyesters with small structural variations improve the mechanical properties of polylactide

Improving the properties of biodegradable polymeric materials is needed to obtain materials competitive with current bulk plastics. Low-molecular weight polyesters with small differences in their backbone were synthesized using a straight-forward method and were subsequently blended with polylactide (PLA). The materials showed an improved ductility of up to 100% points and otherwise retained material properties. The changes in mechanical properties were shown to match the miscibility range of the materials and can be predicted by the solubility parameters of the materials up to a polyester content of roughly 10% w/w. The thermal stability of all the low-molecular weight polyesters was higher than that of PLA, and most 25% w/w blends showed a thermal degradation behavior similar to that of neat PLA. Low-molecular weight polyesters were demonstrated as being potential enhancers of the properties of PLA, while the materials degradability was maintained. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012