Healable and Post-Programmable Metal-Organic Framework-Vitrimer Composites.

Abstract

Metal-organic framework (MOF) particles are commonly incorporated into polymer composites to impart porosity or functionality, but they often remain as fillers rather than defining the polymer network architecture. Here, we report a new design principle in which UiO-66-NH₂ nanoparticles are used as dynamic covalent crosslinkers for a linear polyimines to form MOF-vitrimer composites. Through imine bond formation between MOF-bound amines and polymer aldehydes, the MOF becomes an integral network node, yielding free-standing MOF-vitrimer composite films with high solvent resistance, while the MOF retains crystallinity. This architecture gives rise to properties beyond conventional MOF-polymer composites: dynamic imine exchange enables thermal healing, mechanical reprocessing, and chemical recycling. Furthermore, post-synthetic tempering redistributes network connectivity and reprograms the mechanical properties from soft and extensible to stiff and strong, enabling material pluripotency and tunability to suit different applications. Unlike conventional organic crosslinkers, the MOF nodes also retain their intrinsic functions, allowing the composites to perform aqueous dye adsorption and organophosphate simulant hydrolysis while remaining easy to handle and recover. This work establishes MOFs as multifunctional dynamic crosslinkers for healable, recyclable, and post-programmable hybrid materials, expanding MOF-polymer composites beyond passive filler architectures.