Polyurethanes are obtained by the reaction of polyisocyanates with polyhydroxy compounds, such as polyethers, polyesters, or glycols. Compounds containing groups such as amino and carbonyl may also be used. Thus, typical polyurethanes contain, in addition to urethane groups, aliphatic and aromatic hydrocarbon residues, ester, ether, amide and urea groups. In this review, analytical methods are described for analysis of polar groups and characterization of micro-phase separation structures.