Cast polyurethanes are a diverse and versatile group of materials that are known for abrasion resistance, chemical resistivity, stability in water, ease of processing and relative low cost. Cast polyurethanes are found in almost every industry. Molds for cast urethanes are relatively inexpensive and can be made from a variety of materials.
Cast polyurethanes are a good substitute for a number of materials where improved performance is required. Urethanes can be made as soft as gum rubber or as hard as a golf ball. In fact, most golf balls are polyurethane!
Cast polyurethanes are elastomers and are created by the reaction of a prepolymer which contains reactive isocyanate groups and a curative which contains hydroxyl or amine groups. In their simplest form, these two components, the prepolymer and curative are the only chemicals in the mix. The mixture is then poured into a heated mold where the components react to form a solid elastomeric piece.