Shape memory behaviour of functionalised Poly(?-caprolactone) crosslinked by hexamethylene-diisocyanate

In this study, the shape memory behaviour of poly(e-caprolactone) (PCL) with different crosslinking degrees was investigated. PCL was first functionalised with maleic anhydride (MA) and glycidyl methacrylate (GMA), and successively chemically crosslinked by hexamethylene diisocianate (HMDI). The crosslinking reaction was followed with a rotational stress rheometer, while the shape memory behaviour was analyzed with cyclic thermomechanical experiments and optical microscopy. The results show that the new materials exhibit good shape memory behaviour and good stability of the shape recovery under consecutive cycles in the range 55 - 70°C, can reach high level of stretching, and are furthermore characterised by high recovery speed. These results are promising for potential practical applications, as biomaterials for embolic devices in minimally invasive surgery.