聚醚氨酯红外N—H伸缩振动谱带分析

通过快速淬火实验,直接观察到聚醚氨酯中由硬段N—H基与软段—O—形成氢键的N—H伸缩振动谱带位于约3295cm~(-1),低于与硬段本身C=O形成氢键的N—H伸缩振动谱带(约3330cm~(-1))。这两种氢键键连的N—H伸缩振动谱带的位置从聚醚氨酯-四氢呋喃溶液的红外光谱得到证实。在此基础上讨论了三种聚醚氨酯试样的红外光谱中N—H伸缩振动谱带的差异。

ANALYSIS OF N-H STRETCHING VIBRATION IN INFRARED SPECTRA OF POLYETHER-POLYURETHANE

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