Direct synthesis of α-Carboxyl-ω-Hydroxyl polymers by catalyst and initiator in the same molecule

With the increasing demands on healthy and environmental issues in modern society, green chemistry and atomic economics have become the consensus of researchers and manufacturers, forcing us to explore much simpler approaches to producing widely utilized biodegradable and biocompatible polyesters. In this context, 4-(hydroxymethyl) benzoic acid (4-HBA), an organic weak acid involving carboxyl and hydroxyl groups, was selected to proceed the ROP of various cyclic monomers, such as ε -caprolactone (CL), δ -valerolactone (VL), l-lactide (LA) and trimethylene carbonate (TMC), as catalyst and initiator in the same molecule (CINICAT) to give α -carboxyl- ω -hydroxyl polymers with controlled molar mass and narrow dispersity (around 1.15). MALDI-TOF, 2D-NMR and other characterizations were applied to confirm the structure of the produced polymers, while density of functional theory simulation ( DFT) calculation was carried out to study the structural influence of CINICAT on the polymerizations as well as the polymerization mechanism.