Humanities › History & Culture The History of Polyurethane - Otto Bayer Polyurethane: An Organic Polymer Share Flipboard Email Print History & Culture Inventions Famous Inventions Famous Inventors Patents & Trademarks Invention Timelines Computers & The Internet American History African American History African History Ancient History and Culture Asian History European History Genealogy Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Mary Bellis Inventions Expert Mary Bellis covered inventions and inventors for ThoughtCo for 18 years. She is known for her independent films and documentaries, including one about Alexander Graham Bell. our editorial process Mary Bellis Updated March 17, 2017 Polyurethane is an organic polymer composed of organic units joined by carbamate (urethane) links. While most polyurethanes are thermosetting polymers that do not melt when heated, thermoplastic polyurethanes are also available. According to the Alliance of The Polyurethane Industry, "Polyurethanes are formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with a diisocyanate or a polymeric isocyanate in the presence of suitable catalysts and additives." Polyurethanes are best known to the public in the form of flexible foams: upholstery, mattresses, earplugs, chemical-resistant coatings, specialty adhesives and sealants, and packaging. It also comes to the rigid forms of insulation for buildings, water heaters, refrigerated transport, and commercial and residential refrigeration. Polyurethane products often are simply called “urethanes”, but should not be confused with ethyl carbamate, which is also called urethane. Polyurethanes neither contain nor are produced from ethyl carbamate. Otto Bayer Otto Bayer and co-workers at IG Farben in Leverkusen, Germany, discovered and patented the chemistry of polyurethanes in 1937. Bayer (1902 - 1982) developed the novel polyisocyanate-polyaddition process. The basic idea which he documents from March 26, 1937, relates to spinnable products made of hexane-1,6-diisocyanate (HDI) and hexa-1,6-diamine (HDA). Publication of German Patent DRP 728981 on November 13, 1937: "A process for the production of polyurethanes and polyureas". The team of inventors consisted of Otto Bayer, Werner Siefken, Heinrich Rinke, L. Orthner and H. Schild. Heinrich Rinke Octamethylene diisocyanate and butanediol-1,4 are the units of a polymer produced by Heinrich Rinke. He called this area of polymers "polyurethanes", a name which was soon to become known worldwide for an extremely versatile class of materials. Right from the start, trade names were given to polyurethane products. Igamid® for plastics materials, Perlon® for fibers. William Hanford and Donald Holmes William Edward Hanford and Donald Fletcher Holmes invented a process for making the multipurpose material polyurethane. Other Uses In 1969, Bayer exhibited an all-plastic car in Düsseldorf, Germany. Parts of this car, including the body panels, were made using a new process called reaction injection molding (RIM), in which the reactants were mixed and then injected into a mold. The addition of fillers produced reinforced RIM (RRIM), which provided improvements in flexural modulus (stiffness), reduction in coefficient of thermal expansion and better thermal stability. By using this technology, the first plastic-body automobile was introduced in the United States in 1983. It was called the Pontiac Fiero. Further increases in stiffness were obtained by incorporating pre-placed glass mats into the RIM mold cavity, called resin injection molding, or structural RIM. Polyurethane foam (including foam rubber) is sometimes made using small amounts of blowing agents to give less dense foam, better cushioning/energy absorption or thermal insulation. In the early 1990s, because of their impact on ozone depletion, the Montreal Protocol restricted the use of many chlorine-containing blowing agents. By the late 1990s, blowing agents such as carbon dioxide and pentane were widely used in North America and the EU.