History[edit]

Prof. Otto Bayer in 1952 demonstrating his creation

Otto Bayer and his coworkers at IG Farben in Leverkusen, Germany, first made polyurethanes in 1937.^[4][5] The new polymers had some advantages over existing plastics that were made by polymerizing olefins or by polycondensation, and were not covered by patents obtained by Wallace Carothers on polyesters.^[6] Early work focused on the production of fibers and flexible foams and PUs were applied on a limited scale as aircraft coating during World War II.^[6] Polyisocyanates became commercially available in 1952, and production of flexible polyurethane foam began in 1954 by combining toluene diisocyanate (TDI) and polyester polyols. These materials were also used to produce rigid foams, gum rubber, and elastomers. Linear fibers were produced from hexamethylene diisocyanate (HDI) and 1,4-Butanediol (BDO).