Polyfluorenes: Twenty years of progress

Polyfluorenes are an important class of electroactive and photoactive mater ials. In the last three years this research field has literally exploded be cause of polyfluorenes' exceptional electrooptical properties for applicati ons in light-emitting diodes. This is the only family of conjugated polymer s that emit colors spanning the entire visible range with high efficiency a nd low operating voltage. Other unusual optical and electrical properties a re made possible with polyfluorene derivatives, such as thermochromism and conducting base- doped polyelectrolytes. (C) 2001 John Wiley & Sons, Inc.