Synthetic biodegradable medical polyurethanes

Polyurethanes (PURs) are a class of block copolymers synthesised from three different reagents: a polyol, a di- or multi-isocyanate, and a chain extender. Biodegradable PURs can be synthesised by properly selecting the building blocks with suitable properties for applications in regenerative medicine. The nature and relative amount of hard and soft segments affect the mechanical properties. PURs can be bulk or surface functionalised with biomimetic peptide sequences or natural polymers, affecting cell response and/or the biodegradation rate. PUR particles, fibres, and hydrogels can be designed with a suitable composition for drug encapsulation and controlled release. This chapter offers an overview of the chemistry of biodegradable and biocompatible PURs and reports their application as scaffolds for tissue engineering and carriers for drug delivery.