Controlled preparation of porous scaffolds by gas foaming of heterogeneous blends

Blending two different immiscible polymers is one of the most efficient strategies to prepare materials with improved performances. Recently, this multi-phase systems have been used in tissue engineering aiming at the preparation of porous scaffolds for cell culture. In this study, thermoplastic biodegradable and biocompatible multi-phase blends with co-continuous micro-structures have been prepared by melt mixing poly(s-caprolactone) (PCL) with thermoplastic gelatin (TG), a thermoplastic material prepared by mixing gelatin with glycerol. The blend have been prepared by selecting the composition into the 60/40 to 40/60 wt-% PCL-TG range. Dynamic mechanical analysis was performed in order to asses the achievement of an heterogeneous micro-structure while, gravimetric measurements and scanning electron micrograph analysis, performed after the selective extraction of the different phases, were used to evaluate the co-continuity of the different systems prepared. Finally, the PCL/TG blends have been further processed by the gas foaming technique, in order to create porous materials with well controlled open-pore micro-architectures, suitable as 3D porous scaffolds for tissue engineering applications.