New π-stacked benzofulvene polymer showing thermoreversible polymerization: studies in macromolecular and aggregate structures and polymerization mechanism

The macromolecular and aggregate structures of poly[ethyl 1-methylene-3-(4-methylphenyl)-1H-indene-2-carboxylate] (poly-BF1; a new polymer based on a functionalized benzofulvene moiety showing interesting properties, i.e., thermoreversible polymerization/depolymerization behavior, high solubility in the most common organic solvents, and susceptibility to molecular manipulation) have been investigated with NMR spectroscopy, absorption and emission spectrophotometry, and transmission electron microscopy (TEM). Moreover, the polymerization mechanism has been studied to obtain further information on the polymer structure. The collected evidence is consistent in indicating for poly-BF1 a vinyl (1,2) polymer structure stabilized by means of aromatic stacking interactions. Furthermore, TEM studies performed on metal replicas have shown that the polymer is liable to give nanostructured aggregates