Effect of the Chemical Modification on the Thermal and Rheological Properties of Different Polylactides for Foaming.

Polylactide (PLA) is one of the most important bioplastics on the market with a permanent growth in production capacity. Due to its good mechanical properties, it is comparable to polystyrene. But in terms of foaming the melt strength and extensibility of commercial polylactide are rather low. Therefore such commercial grades often need to be chemically modified to induce crosslinking, chain extension or grafting by means of reactive extrusion on a twin-screw extruder. In this work different polylactide grades were used, to better understand the influence of the molecular characteristics, such as molecular weight, acid value and D-content, not only on the modification mechanism, but also on the foam properties. [ABSTRACT FROM AUTHOR]