Structural characterization of oligomers from the polycondensation of citric acid with ethylene glycol and long-chain aliphatic alcohols

摘要

The structural characterization of polyesters of citric acid (CA) with ethylene glycol and long-chain aliphatic alcohols (ROH), prepared by the composition of the reaction mixture being adjusted slightly away from stoichiometric equivalence, was performed with H-1- and C-13-NMR spectroscopy. The aliphatic alcohols employed were I-decanol, 1-dodecanol, and 1-octadecanol. The C-13-NMR carbonyl region presented four groups of signals, two corresponding to the ester groups and two corresponding to the acid groups. However, symmetric and asymmetric groups of CA moieties were identified in the C-13-NMR spectra. The ester yield from ROH decreased as the number of carbon atoms in the alcohols increased. (C) 2003 Wiley Periodicals, Inc. [References: 7]