This article describes the synthesis of a new glycerol-based AB(2) type monomer-ethyl[3-[2-hydroxy-1-(hydroxymethyl)ethoxy]propyl]thioacetate (4) and its application for the preparation of hyperbranched polyesters. The polycondensation of 4 has been performed over a wide range of catalysts and reaction conditions leading to polymers containing solely primary hydroxyl groups. The polycondensation progress has been monitored by means of H-1 NMR. The degree of branching of the polymers showed to be in the range of 0.5 +/- 0.03. The obtained polyesters easily undergo hydrolysis or alcoholysis and may be of interest as recycled materials.(C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3860-3868, 2009