Synthesis and assembly of novel poly(organophosphazene) structures based on noncovalent "host-guest" inclusion complexation

The design and assembly of new organophosphazene polymeric materials based on supramolecular "host-guest" interactions was accomplished by linkage of supramolecular coupling units to either the main-chain terminus or the side-chains of the parent phosphazene polymer. Noncovalent interactions at the main chain terminus were used to produce amphiphilic palm-Tree like pseudoblock copolymers via host-guest interactions between an adamantane end-functionalized polyphosphazene and a 4-armed β-cyclodextrin (β-CD) initiated poly[poly(ethylene glycol) methyl ether methacylate] branched-star type polymer. Moreover, noncovalent interactions involving polymer side-chains were achieved between polyphosphazenes with β-CD pendant units and other polyphosphazene molecules with adamantyl moieties on the side-chains. These new organo-phosphazene structures based on noncovalent "host-guest" interactions generate new opportunities for the macromolecular modification of polyphosphazenes. The resultant materials demonstrated useful properties including self-aggregation, supramolecular gelation, and stimulus-responsive behavior.