Red and deep-red emissive polymeric nanoparticles based on polybenzofulvene and perylenediimide derivatives

Polymeric nanoparticles obtained by co-aggregation of a polybenzofulvene derivative with bulky substituted perylene diimide dyes in tetrahydrofuran/water mixtures display emission color tunable from blue to red, or deep-red, thanks to energy transfer processes from the polymer to the emissive dyes activated by nanoparticle shrinking. At high water concentrations the presence of well emissive perylene diimide dye micro-aggregates within the polymer nanoparticles limits the FRET efficiency leading to a combined emission from both the polymer (blue) and the dyes (red and deep-red). The optical properties of the NPs are retained also in the solid state where a weak blue contribution of the polymer emission is observed providing multicolor emission in the films obtained by NPs deposition