FAR-INFRARED SPECTRA OF SOME SEGMENTED POLYURETHANES

The aim of this work is the direct observation of hydrogen-bond vibrat ions in urethane compounds by far-infrared spectroscopy. The spectra ( 30-400 cm(-1)) of some polyurethanes have been investigated. A compara tive analysis of these data and preliminary results on the low-frequen cy infrared spectra of a series of low-molecular-mass crystalline diur ethanes and oligobutadiene urethanes are presented. We found that the bands are sensitive to intermolecular interactions. The assignment of the bands located at 80-100 and 130-200 cm(-1) to the hydrogen-bond vi brational mode and a torsional mode around the C-N bond, respectively, is proposed.