Hole-transporting properties of organosilanylene–diethynylpyrene and diethynylanthracene alternating polymers. Applications to patterning of light-emitting images

Diethylsilanylene- and tetramethyldisilanylene-1,6-diethynylpyrene alternating polymers (1 and 2) were prepared by the reactions of 1,6-di(lithioethynyl)pyrene and the respective dichloroorganosilanes. The hole-transporting properties of the resulting polymers were evaluated by the performance of electroluminescent (EL) devices with the structure of indium–tin–oxide/polymer/Alq/Mg–Ag, in comparison with those of an organosilanylene-9,10-diethynylanthracene alternating polymer (3), reported previously. Among them, the device with polymer 1 exhibited the best performance with a maximum luminescence of 6000 cd m−2, which increased to 16 000 cd m−2 when electron-blocking TPD layer was introduced between the polymer and Alq layers. Polymers 1–3 were found to be photoactive and irradiation of the polymer films with a UV lamp led to a drastic drop of the luminance of the device, being applicable to the patterning of EL images.