Electrosynthesis of thin films of polythiophenes containing pyrene groups and flexible spacers, useful in the preparation of graphene polymer composites

Abstract

Thin polythiophene films were prepared by electrodeposition, using two novel thiophene monomers containing a pyrene unit linked via a flexible spacer. The obtained polymers have a suitable architecture for the further preparation of polymer composites with graphene via π-π interactions. Physicochemical characterization of the precursor polymers demonstrated that the resulting films are made of homogeneous electroactive polythiophene with pendant pyrene units regularly located on the polymer surface. These compounds are highly emissive and easily form excimers as other high pyrene content polymers. The polymer emission can be drastically quenched by the interaction with graphene after dipping the film into an aqueous suspension of reduced graphite oxide. The presence of aggregated graphene onto pyrene rich content areas by non-covalent interactions has been confirmed by AFM analysis. This kind of polythiophene/pyrene thin films showed to be a good matrix for the elaboration of fluorescent polymer composites.