Abstract: Arelatively high degree of physical crosslink was inferred from the superior mechanical properties of thermoplastic polyurethane elastomers(TPU). For the most part, this has been assumed due to hydrogen bonding. In this paper hydrogen bonding effects in some thermoplastic polyurethane elastomers, consisting of poly(tetramethylene oxide) of M_n=2000, 4,4'-diphenyl methane diisocyanate and extenders: N-methyl diethanol amine,1,4-butandiol and 1,2-ethylene diamine, have been studied by using dynamic mechanical analysis. The activation energies of hydrogen bonding dissociation and the physical crosslink densities have been evaluated from the elastic modulus temperature relation of the TPUsamples.

Key words: Thermoplastic polyurethane elastomers, Hydrogen bonding, Physical crosslink, Temperature dependence