Abstract: A method for preparing biodegradable polyurethanes includes contacting a flowable quasi-pre-polymer including free aliphatic polyisocyanate compounds with a polyester polyol hardener having a functionality of at least two to form a reactive liquid mixture. The quasi-prepolymer can, for example, be formed by contacting a polyisocyanate component comprising at least one aliphatic polyisocyanate compound with a polyol component comprising at least one polyol compound to form an adduct of the polyisocyanate component and the polyol component wherein a sufficient excess of the polyisocyanate component is used to form the quasi-prepolymer.