1H and 13C NMR determination of the hydroxy end-groups in poly(oxypropylene)s

Abstract

1H and 13C NMR signals of tri(propylene glycol) and of its benzoate and phenyl urethane were assigned by means of 1D and 2D NMR methods such as super-selective long-range INEPT, H-H COSY, H-C COSY and H-H-C RCT spectra. Both 1H and 13C NMR were used as methods for the determination of primary and secondary hydroxy end-groups and of their degree of conversion. 13C NMR was found to be a reliable and universal method of end-group determination even for cases where 1H NMR fails due to the presence of water in the sample or to the nature of the reactant. The results are applied to the analysis of poly(oxypropylene)s with two or three hydroxy end-groups and their derivatives.