Study of the in vitro degradation of poly(ethyl glyoxylate)

In vitro degradation of poly(ethyl glyoxylate) (PEtG), a functionalised polyacetal, was investigated. First, the thermodynamic polymerization parameters and the ceiling temperature (Tc) were determined (ΔHp = 28 ± 3 kJ mol−1, ΔSp = 98 ± 7 J mol−1 K−1, Tc = 310 ± 4 K). Secondly, PEtG hydrolysis was investigated using potentiometry, weight loss measurements, SEC and 1H NMR. The results show that PEtG is stable for at least 7 days in aqueous media. Then degradation occurs and releases ethanol and glyoxylic acid hydrate as final products. A scheme for the degradation mechanism involving chain scission and ester hydrolysis is proposed.