Biodegradable shape-memory polymers using polycaprolactone and isosorbide based polyurethane blends.

Thermally responsive shape-memory polymers have received widespread attention in the biomedical field. In this study, biocompatible and biodegradable polyurethane (PU) and polycaprolactone (PCL) were blended to obtain shape-memory properties. Highly crystalline PCL was used as a hard segment, and PU synthesized from isosorbide, which is non-toxic and chemically and thermally stable, was used as a soft segment. The obtained PU/PCL blends containing the 30%, 50%, and 70% PU by weight were investigated for their thermal properties, mechanical properties, and shape-memory behavior. The 30%PU/PCL polymer has the best shape-memory characteristics and can be knotted by itself in the hot water bath, indicating that it can be applied in smart suture applications. The degradation test performed at 37 °C in phosphate buffered solution showed a mass loss of 2-4% for the obtained PU/PCL blends after 6 weeks. Finally, MC3T3-E1 cells cultured on PU/PCL blends showed high biocompatibility due to high adhesion and proliferation.