Degradable polymers from ring-opening polymerization of α-angelica lactone, a five-membered unsaturated lactone

A degradable polymer was prepared from alpha-angelica lactone, a five-membered unsaturated lactone, by ring-opening polymerization (ROP). The polymerizability of alpha-angelica lactone was explained by a DFT calculation. The degradability of the resultant polymer and the reaction kinetics of alpha-angelica lactone ROP were also considered. Owing to the presence of a C=C bond in alpha-angelica lactone, the ROP of five-membered cyclic lactone becomes feasible under moderate conditions and the resultant polyester exhibits good degradability under light or acidic/basic circumstances. Since alpha-angelica lactone can be easily obtained from the commercially available green bio-platform chemical levulinic acid, its ROP may provide a potential route to produce functionalized aliphatic polyesters from renewable resources.