These polymers first appeared on the market in Germany around 1941. A typical chain repeat unit of polyurethanes is:

They are synthesized by polyaddition of diisocyanates and low molecular weight polyethers or polyesters with hydroxyl end groups.

Most common uses include flexible or rigid foam for furniture, elastomers and plastics for automobile industry, leather and wood substitutes in the manifacture of coverings, shoe soles and sports equipment.