A perspective into ring-opening polymerization of ε-caprolactone and lactides: effect of, ligand, catalyst structure and system dynamics, on catalytic activity and polymer properties

Polylactic acid (PLAs) and polycaprolactones (PCLs) are emerging to be polyesters of choice because they are biodegradable and biocompatible. The industrial viable method currently used for their production is catalytic ring-opening polymerization (ROP) of their respective cyclic ester monomers. The catalyst is at the core of ROP chemical transformation and as such research is dedicated towards the innovation of more efficient and selective catalysts. Catalyst structural features greatly influence catalyst performance in ROP, and this review discusses the effects of ligand and catalyst structure and system dynamics, on catalytic activity and polymer properties. The effects of associated catalyst components such as initiating groups, ligand chirality, and stereochemical in relation to catalyst activity and polymer properties were also reviewed. The effects of metal nuclearity and catalyst flexibility on catalytic activity were also reviewed. The effect of solvent and temperature was briefly considered.