Degradation of poly(5-hydroxy-trimethylene carbonate) in aqueous environments

Poly(5-hydroxy-trimethylene carbonate) (PHTMC) was synthesized through ring-opening polymerization of 5-benzyloxy trimethylene carbonate followed by debenzylation. The water solubility of the resulting homopolymer was measured as a function of its molecular weight, and its degradation in acidic (pH 2.0), and basic (pH 12.0) solutions of deionized water, as well as in phosphate buffered saline (PBS, pH 7.4) assessed. PHTMC exhibited notable hydrophilicity, even at molecular weights as high as 49 kDa. The pendant hydroxyl functional groups also allowed PHTMC to degrade rapidly (<1 h) under basic conditions via an intramolecular cyclization process along the polymer backbone. The ultimate degradation products were the biologically benign glycerol and carbon dioxide. (C) 2018 Elsevier Ltd. All rights reserved.