Host-guest complexation: a convenient route to polybithiophene composites by electrosynthesis in aqueous media. Synthesis and characterization of a new material containing cyclodextrins

An inclusion compound with hydroxypropyl-beta-cyclodextrin (HP beta CD) as host molecule has been used to electropolymerize bithiophene in aqueous med ium. The complexation of bithiophene by HP beta CD has been investigated by fluorescence, showing that BT molecules are tightly bound to cyclodextrin hosts. The electrochemical behaviour of this inclusion compound is irrevers ible in aqueous solution in the presence of HP beta CD. The anodic electrop olymerization of the BT-HP beta CD complex has been performed in aqueous me dium under galvanostatic or potentiodynamic conditions. Characterization of the deposited films supports the notion that polybithiophene (PBT) composi tes are formed. Although they show the usual features of PBT, the structure of the films appears to be considerably modified by the presence of cyclod extrins within the material but not grafted onto the polymeric backbone.