Sol-gel process-influence of ageing on the textural properties of organosilsesquioxane materials

Two [thiophene-1,6-dithienylhexa-1,3,5-triene] copolymers were prepared by a palladium catalysed coupling reaction of a dibromothiophene derivative and a bis(tributylstannyl) derivative of a 1,6-dithienylhexa-1,3,5-triene unit. The electrochromism and the photoluminescence properties of the highly conjugated polymers were studied. In the solid state the polymers have strong photoluminescence bands at 2.0 eV for 9 and 1.95 eV for 8. Polymer 8 seems particularly promising for use as a red-light emitting diode, and the two polymers 8 and 9 exhibit red-pale blue electrochromism that makes them suitable for fabricating new devices.