Journal of Material Sciences & Engineering

Bulk Compounding of PCL-PEO Blends for 3D Plotting of Scaffolds for Cardiovascular Tissue Engineering

Abstract

Kim Ragaert, Maeyaert G, Martins CI and Cardon L

3D plotting of micro-extruded filaments is a promising method for the additive manufacturing of porous scaffolds (for tissue engineering) in thermoplastic polymers. A much investigated polymer for degradable scaffolds is poly-ε- caprolactone (PCL). One of the remaining issues with the material is its inherent hydrophilicity, which leads to nonspecific protein adsorption. Specifically for cardiovascular applications, it has also been found that PCL is insufficiently flexible to mimic the mechanic-elastic behavior of the natural tissue. Earlier research has shown that blending with low molecular weight poly-ethylene-oxide (PEO) may offer an improvement in terms of both hydrophilicity and flexibility. Until now, solution-based blending has been used as a manufacturing method for these blends, since PCL and PEO are largely immiscible in the melt. This, however, is tedious work which yields only a few grams of material at a time. Therefore, in the current research, a method has been developed for the bulk compounding of PCL-PEO blends, using a twin-screw extruder. The manufactured blends were evaluated for composition, dispersion of the PEO and crystalline morphology. It was found that by re-compounding the blends after the first extrusion step, a good dispersion of the PEO within the PCL matrix was achieved.