Polyurethanes (PUs) are an important class of thermoplastic and thermoset polymers obtained by polycondensation reactions among different polyols, isocyanates and chain extenders, leading to a wide variety of polymers with many different properties and applications. In this book, the authors present current research in the study of the properties, structure and applications of polyurethane. Topics include polyurethanes in analytical chemistry applications from sorbent foams to conductive materials and sensors; biomedical polyurethane-based materials and blocked polyurethanes in x-ray shielding and electrically conductive adhesives.