*2.5. Migration of Plasticizer by Solvent Extraction Test*

Migration test was studied by solvent extraction using n-hexane solvent as is indicated by several reports [36,38,39]. Samples of PLA and PLA plasticized with ECO were immersed in n-hexane solvent at different temperatures (30, 40, 50, and 60 ◦C) over 8 h in an air circulating oven mod. Selecta 2001245 by JP Selecta S.A. (Barcelona, Spain). Before and after experiments, all samples were dried at 40 ◦C for 24 h to ensure the absence of solvent. The weight loss of plasticizer (*WLp*) obtained by migration test was calculated using Equation (3).

$$\mathcal{W}L\_p\left(\%\right) = \frac{w\_b - w\_a}{w\_b} \cdot 100\tag{3}$$

where *w<sup>b</sup>* is the weight of samples before experiment and *w<sup>a</sup>* is the weight after migration test.
