observed in all PLAeOLA formulations. In order to assess this
possibility, thermal properties of aged samples at different storage
times were investigated by DSC (Fig. 5). These curves showed that
neat PLA and those formulations with 15 wt% OLA suffered physical
ageing since the presence of an endothermic peak at Tg gives an
indication of the relaxation of materials stored at temperatures
below Tg. The area of such peak corresponds to the relaxation
enthalpy (DHr), which increased with storage time in particular for