N-H stretching regions of Infrared spectra of polyether urethane polymers prepared by a two-step or one-step polymerization reaction have been compared and their differences indicate the existence of differences in the frequecy and the amount of N-H

-O- and N-H.. ..O=C hydrogen bonding formed. Quenching to Lower temperature to retain the degree of phase mixing at the elevated temperature

N-H stretching vibration at 3295 cm-1 which is hydrogen bonded with -O- of soft segments and the vibration hydrogen bonded with -O-of soft segents and the vibration hydrogen bonded with C=O of hard segments at 3330 cm-1 have been directly observed. The frequency at 3295cm-1 of N-H stretching vibration hydrogen bonded with -O- has been confirmed by the spectrum of polyether urethane dissolved in THF solvent.