Coating the Right Polymer: Achieving Ideal Metal-Organic Framework Particle Dispersibility in Polymer Matrixes Using a Coordinative Crosslinking Surface Modification Method.

This work describes the first generalizable method to modify various metal-organic framework (MOF) surfaces with polyimide, polysulfone, polycarbonate, and polymer of intrinsic microporosity-1 (PIM-1). The method first utilizes electrostatic adsorption to rapidly decorate positively charged MOF surfaces with a layer of negatively charged metal-organic nanocapsule, PgC5 Cu. After mixing with the polymer, the copper open metal sites on PgC5 Cu can coordinatively crosslink the polar functional groups on the surface polymer upon thermal activation thereby resulting in the immobilization of a uniform sub-10 nm polymer coating. We quantitatively analyzed the distribution of free path spacing between MOF particles and demonstrated that when the surface polymer matches the matrix polymer, the MOF dispersion was not only visually improved but also found to align perfectly with a theoretically predicted ideal dispersion model where no aggregation driving force was present.