Thermoplastic (Linear) Polyurethane Elastomers

Abstract

Thermoplastic urethane elastomers have become well-established commercial materials since their inception in the BF Goodrich research laboratories in the 1950s by Schollenberger et al. Thermoplastic urethane elastomers are at the same time thermoplastic and highly elastic rubbers. They consist of essentially linear primary polymer chains. The structure of these primary chains comprises a preponderance of relatively long, flexible chain segments which have been joined end-to-end by rigid chain segments through covalent chemical bonds. The flexible segments are diisocyanatecoupled, low-melting polyester or polyether chains. The rigid segments include single diurethane bridges resulting when a diisocyanate molecule couples two polyester or polyether molecules, but more particularly they are the longer, high-melting urethane chain segments formed by the reaction of diisocyanate with the small glycol chain-extender component.