What is Polyurethane?

According to the Alliance for the Polyurethanes Industry (API), “Polyurethanes are formed when a polyol reacts with a diisocyanate or a polymeric isocyanate when there are suitable catalysts and additives present.“ Polyurethane products are thermoset materials, meaning they cannot be continuously melted and reshaped into new products as can be done with thermoplastics. Recycling technology does exist for many polyurethane products.

Producing polyurethane parts involves a chemical reaction whereby specific polyols, isocyanates and additives are added together in specific quantities under specific conditions to produce a polyurethane product with the properties required for that application. Many of these components are in liquid form before they are combined and react with one another.

Many polyurethane products – such as polyurethane foams – are made by combining two types of monomer units – isocyanates and polyols. You combine these separate monomers to make the polyurethane polymer. Isocyanates are often called Component A, and polyols are often called Component B. Together, Components A and B make up a polyurethane system, that is, the main ingredients needed to produce the polyurethane.

The basic reaction to make polyurethanes is:

    isocyanate (component A)

+ polyol (component B)

  polyurethane + heat

To learn about the processing machinery used to produce polyurethane products, visit our Hennecke Machinery subsidiary.

Bayer – Where Polyurethane Chemistry Was Invented

The basic principle for polyurethane chemistry was invented in 1937 in the research laboratories of Bayer AG. Dr. Otto Bayer was working in the Central Research Department of Bayer's Leverkusen, Germany headquarters and discovered polyurethane chemistry while pursuing other polymer innovations. He later became Head of Research at Bayer AG. Within years, polyurethane chemistry became an exciting new branch of polymer chemistry that has contributed many products to everyday living. From furniture cushioning to energy-saving building and appliance insulation to highly durable elastomers for industrial parts, polyurethane chemistry is rooted in the innovative developments of Bayer. And the innovation continues today at Bayer MaterialScience.