Preparation and properties of flexible poly(lactic acid) blend foams

High-performance poly(lactic acid) (PLA) foam has been recognized as a promising material because of its biodegradability. However, low flexibility and foamability of PLAs has limited its use in different fields. In this study, a blend-toughening technology was used to toughen PLA and prepare flexible foams. The mechanical properties of PLA blends were evaluated, and the cellular structure of these foaming blends was characterized. The results show that the blending components significantly affected the overall mechanical properties and foaming behavior of PLA. The toughness of PLA was enhanced by adding poly(butylene adipate-co-terephthalate) (PBAT) and rigid particles. The rheological behavior of PLA was also affected by adding PBAT. Therefore, the cellular structure of the PLA foams was affected. A constitutive model was also used to fit the experimental results of the compression property of the PLA foam.