Characterization of polycaprolactone and starch blends for potential application within the biomaterials field

Abstract

Thermally blending starch and polycaprolactone with the compatibilizer methylenediphenyl diisocyanate (MDI) distributed in the polyester phase had been previously confirmed to enhance the mechanical properties and interface between the two phases of the blends. In this study, blends of polycaprolactone with various levels of starch and 1.0% MDI were prepared through melt blending using a twin-screw extruder, and an extensive characterization including mechanical properties, microstructure, melting, thermo-mechanical behaviour, hydrophilicity and degradation in Hank’s solution were further carried out, aiming at an alternative for orthopaedic applications. The results demonstrated that MDI had improved the mechanical properties of polycaprolactone (PCL) and starch blends, but an optimal ratio of starch level and MDI content was required, which had been found to be 1.0 wt % MDI with 30 wt % starch content. The present study indicated the starch and polycaprolactone blends may present a significant potential for biomedical applications.

Key words: Polycaprolactone, starch blends, biomaterials.