13C‐NMR spectroscopy study of polyurethane obtained from azide hydroxyl‐terminated polymer cured with isophorone diisocyanate (IPDI)

Chemical structure investigations of polyurethane binders based on difunc- tional linear glycidyl azide polymer (GAP) cured with isophorone diisocyanate (IPDI) were performed using 13 C-NMR spectroscopy in solution. Chemical functions such as urethane, urea, allophanate, and biuret were all expected to be detected in these poly- meric binders. 13 C-NMR assignment of the C|O urethane and urea functions were found in these polymers as determined by using model compounds of IPDI. The 13 C- NMR data gathered in this article can be considered as basic parameters for further characterization of polyurethane structure based on IPDI. Also, 13 C CP MAS NMR spectra of GAP-IPDI-based polymers were carried out to identify the various chemical functions present in solid polyurethane elastomer. In addition, the curing evolution of a GAP-IPDI-based polymer at 50 and 807C in bulk was monitored, and the reaction path of the binder was readily determined. Some conclusions on the effects of the cure catalyst and the curing temperature were also drawn. q 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2991-2998, 1997