Extended liquid-crystalline oligofluorenes with photo- and electroluminescence

In this paper we report the synthesis and characterization of a series of low-molecular weight light-emitting molecules based on short oligofluorene cores, from one to three 9,9-dioctylfluorene units, elongated at the 2- and 7-positions by means of promesogenic units. The effect of this structural modification on the mesomorphic properties, as well as on the optical and electrochemical properties, is studied. The possibility of using these molecules as emitters in light-emitting diodes (LEDs) and polarized photoluminescent layers has been explored.