Introduction to Polyurethane Chemistry

Polyurethanes have improved the quality of modern life due to a large number of applications such as insulation foams in houses and buildings to control temperature, flexible foams in car seats and furniture, dampers in shoes for comfort, and coatings to protect wooden and metallic materials or simply to improve aesthetics, packing, and medical devices. Understanding the structure–property relationship of polyurethane is a key element in designing new materials with improved properties. Due to various requirements, ranging from physical behavior to chemical properties to novel applications and sustainability, polyurethane chemistries and technologies are rapidly responding to and adopting such changes and needs. This chapter discusses some of the important topics of polyurethanes including their chemistry, mechanism, and synthesis of new materials (such as polyols and isocyanates). It also discusses the role and variety of other ingredients—such as chain extenders, cross-linkers, catalysts, and additives—to understand how they can influence the overall properties of polyurethanes. Some examples of advances made in polyurethanes, and broader perspectives about their chemistry and technology, are provided.