Peripheral carbazole or cyano substitutents in poly (aryl ether) based bipolar polymeric hosts: Increase the hole or electron injection properties for blue phosphorescent polymer light emitting diodes

Abstract

A series of poly (aryl ether) based bipolar polymer hosts, PCzOPOC8, PCzOPOCz, and PCzOPOCN with a peripheral carbazole or cyano unit which joins the main chain by a nonconjugated linker of a hexyl group, were synthesized and characterized. They depicted high triplet level (E T) (>2.80 eV), which was probably attributed to oxygen-interrupted nonconjugated main chains of polymers as well as carbazole and phosphine oxide groups with high E T. While doped with a 10 wt% typical blue phosphor {iridium(III)[bis(4,6-difluoro phenyl)pyridinato-N, C2]picolinate, FIrpic)}, compared with those of nonsubstituted PCzOPOC8 and peripheral cyano-substituted PCzOPOCN, PCzOPOCz with carbazole moiety gave better performances due to balance of carrier flux from carbazole moiety with good hole transport ability.

Application of Self-Assembled Polyarylether Substrate in Flexible Organic Light-Emitting Diodes

“…PMMA (Mw = 350,000 g mol −1 , Sigma Aldrich, Gillingham, UK) was dissolved in N , N -dimethylformamide (DMF, Sigma Aldrich, Gillingham, UK) to obtain a transparent polymer solution with a concentration of 12 wt%. The polymer was dissolved at 55 °C using the magnetic stirrer plate, set at a rotation speed of 700 rpm (IKA RCT basic, Staufen, Germany) for 2.5 h [ 15 , 16 ].…”

“…PMMA (Mw = 350,000 g mol −1 , Sigma Aldrich, Gillingham, UK) was dissolved in N,N-dimethylformamide (DMF, Sigma Aldrich, Gillingham, UK) to obtain a transparent polymer solution with a concentration of 12 wt%. The polymer was dissolved at 55 • C using the magnetic stirrer plate, set at a rotation speed of 700 rpm (IKA RCT basic, Staufen, Germany) for 2.5 h[15,16].Polymer material P4 is dissolved in DMAC or NMP solvent in proportion to the required experimental amount to prepare a 10 wt% solution. To do this, the mixture is heated in an oven at 60 • C for one to two days to ensure complete dissolution.…”