The TPU of this invention contains unsaturation in its polymeric backbone. The unsaturation can be present in the 
soft segment or in the hard segment or in both the soft and hard segments of the TPU. The TPU can be molded like a 
thermoplastic, and can be subsequently crosslinked by 
exposure to 
electron beam 
irradiation into thermoset articles having excellent 
chemical resistance, dimensional stability, set properties, 
heat resistance, oxidative resistance, and 
creep resistance. In one embodiment, the TPUs of this invention are the 
reaction product (1) a hydroxyl terminated intermediate, (2) a polyisocyanate, (3) a saturated glycol chain 
extender, and (4) a glycol chain 
extender containing carbon-carbon double bonds, such as the allyl moieties present in 
trimethylolpropane monoallyl 
ether. In another embodiment of this invention, the 
thermoplastic polyurethane which is crosslinkable by e-beam 
irradiation is comprised of the 
reaction product of (1) a saturated hydroxyl terminated intermediate, (2) an unsaturated hydroxyl terminated intermediate, wherein the unsaturated hydroxyl terminated intermediate contains carbon-carbon double bonds, (3) a polyisocyanate, and (4) a saturated glycol chain 
extender.