C60–Polymer Nanocomposite Networks Enabled by Guest–Host Properties

A modular approach for the synthesis of polymer networks with well-defined node and cross-linking dimensions is described. Each node or tie point in the network is a cyclodextrin molecule, which imparts discrete molecular guest–host capabilities to the network. C60 fullerenes homogeneously intercalate in the network, presumably via van der Waals guest–host interactions with the hydrophobic γ-cyclodextrin cavity, resulting in stable C60-filled polymer networks with improved mechanical properties. Networks prepared with α-cyclodextrin, whose inner cavity is smaller than γ-cyclodextrin, and smaller than the C60 diameter, do not yield materials with stable C60 intercalation. Characterization of the final composites reveals that the cross-linked γ-cyclodextrin-based composites maintain stable C60 concentrations, even after multiple extractions with toluene, which itself is a good solvent for C60. Membranes prepared from the cyclodextrin polymer network, prior to C60 intercalation, should also be useful for C60...