This book emphasizes mainly on polyurethanes, raw materials to synthesize it, its applications and synthesis of polyurethane-based block copolymers. Polyurethanes are arguably the most multifaceted family of polymers. Polyurethanes can be prepared range from soft elastomeric polymers to hard elastoplastics. Polyurethanes are used as structural materials, coatings, adhesives, hydrogels and sealants. This book presents the details of polyurethane synthesis and its chemistry, preparation of different kinds of polyurethane ionomers and block copolymers.