Reconfigurable transient polymer networks based on heteroleptic metal–ligand complexes

Abstract

We present a polymer network platform based on metal–ligand complexes that enables reconfiguration through the sequential introduction of polymeric ligands and metal ions. Using tetraPEG functionalized with sterically demanding and slim ligands, we demonstrate four network states. However, the interference from competitive parallel complexations is reflected in rheology as additional relaxation modes. A simple kinetic model rationalizes the extent of reconfiguration as a function of thermodynamic preference, revealing the critical role of competitive complexation. DFT calculations confirm that ligand denticity stabilizes heteroleptic complexes and drives the reconfiguration pathway. Together, experiment, modeling, and computation establish a comprehensive framework for designing reconfigurable transient polymer networks.