In order to obtain homogeneous mixtures of PEtOx and polyperoxide (10, 15 and 20 wt. % of polyperoxide with respect to PEtOx), the polymers were dissolved in chloroform (5 wt. %). A homogeneous viscous solution was obtained after stirring continuously for 3-4 h at room temperature. Subsequently, the solvent was removed under reduced pressure to obtain a fine polymer blend which was ground into a powder. The obtained polymer powder (m = 0.2 g) was pressed into thin discs using a manual hydraulic press (Specac) applying 15 tons of pressure. Melting and crosslinking of polymer discs was performed at different temperatures and for predetermined times in a vacuum oven (BINDER GmbH, Germany).