Lanthanum heterocyclic Schiff-base complex initiated ring-opening polymerization of ɛ-caprolactone

Lanthanum complex supported by the heterocyclic Schiff-base ligand of N-(2-pyridyl)-3,5-di-tert-butyl-salicylaldimine was prepared and employed for the ring-opening polymerization (ROP) of ɛ-caprolactone (ɛ-CL). The polymers obtained with this initiator showed a unimodal molecular weight distribution implied that only one active species was present. Mechanism study revealed that the polymerization proceeds via acyl-oxygen bond cleavage.