From polymer blends to a block copolymer: Ring-opening polymerization of L-lactide/ε-caprolactone eutectic system

In this work, we provide new insights into the ring-opening polymerization (ROP) of eutectic mixtures of L-lactide and ε-caprolactone that lead to the synthesis of polymer blends and a block copolymer. The influence of a set of parameters is studied to produce polyesters with tunable average-molecular weight, crystallinity, and polymer architectures with controlled degradation profiles. The outcome depends on the selection of organocatalysts, including 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN), a new catalyst for the L-lactide/ε-caprolactone eutectic mixture ROP that enabled increasing the polymerization temperature. The mild polymerization temperatures and solventless conditions stand as green features of the ROP here described to prepare resorbable biomaterials with programmable degradation profiles.