Fluorene/carbazole alternating copolymers tethered with polyhedral oligomeric silsesquioxanes: Synthesis, characterization, and electroluminescent properties

摘要

A series of novel fluorene/carbazole alternating copolymers tethered with polyhedral oligomeric silsesquioxanes (POSS), which have well-defined architectures and similar polymerization degrees, are synthesized by the Heck coupling reaction to investigate the effects of the number and the position of POSS on the optoelectronic properties. The introduction of POSS results in blue shifts in the photoluminescence (PL) emission spectra (especially for P2) and improved thermal spectral stability. Moreover, an appropriate amount of POSS is beneficial for enhancing the electroluminescent properties, and a better performance is obtained when POSS units are tethered to the 9-position of the carbazole units, rather than fluorene units. Moreover, POSS facilitates the balance of electron and hole fluxes.