Abstract
Polyether containing electronically isolated carbazolyl fragments and its model compound were synthesized and characterized. Weight-average molecular weight of the polymer was 31,500 with polydispersity index of 2.4. Both the compounds represent amorphous materials of high thermal stability with glass transition temperatures of 137 °C for polymer and of 41 °C for model compound. The derivatives were tested as host materials in green as well as blue phosphorescent OLEDs. The green device with polymeric host exhibited turn-on voltage of 3.3 V, a maximal current efficiency of 11.5 cd/A and maximum brightness of 1312 cd/m 2 . An efficient blue OLED using the model compound as host demonstrated a turn-on voltage of ca. 4.3 V, a maximum brightness of 6225 cd/m 2 , and maximum current efficiency of 23.3 cd/A at 100 cd/m 2 . © 2012 Elsevier B.V.