THIS INVENTION RELATES TO BIOCOMPATIBLE, BIODEGRADABLE THERMOPLASTIC POLYURETHANE OR POLYURETHANE/UREAS COMPRISING ISOCYANATE, POLYOL AND A CONVENTIONAL CHAIN EXTENDER AND/OR A CHAIN EXTENDER HAVING A HYDROLYSABLE LINKING GROUP AND THEIR USE IN TISSUE ENGINEERING AND REPAIR APPLICATIONS, PARTICULARLY AS STENTS AND STENT COATING.