Kuo, Chao-HuiChao-HuiKuoPeng, Kang-ChunKang-ChunPengKuo, Li-ChungLi-ChungKuoYang, Kuei-HuiKuei-HuiYangJIUN-HAW LEEMAN-KIT LEUNGKUO-HUANG HSIEH2008-12-032018-06-282008-12-032018-06-28200608974756http://ntur.lib.ntu.edu.tw//handle/246246/87314https://www.scopus.com/inward/record.uri?eid=2-s2.0-33748532790&doi=10.1021%2fcm060124w&partnerID=40&md5=ec4d9accaedeebd96e3008892ba9c49bA novel family of hole-transport polyurethanes (PUs) has been developed. The PUs were prepared from the condensation polymerization of isophorone diisocyanate (IPDI) with (E,E)-1,4-bis(2-hydroxystyryl)benzene, an oligo p-phenylene-(E)-vinylene (OPV) unit, and various amounts of 2,5-bis(4- hydroxyphenyl)-1,3,4-oxadiazole (OXD), as well as with 4-tert-butyl phenol as the terminal group. The PUs demonstrates superior properties that were concluded on the basis of the improved current injection in the corresponding hole-only device. The OLED device with the OPV-PU interfacial layer inserted in ITO/PEDOT:PSS(20 nm)/PU(30 nm)/α-NPB(10 nm)/Bebq2(20 nm)/Ca(10 nm)/Ag(100 nm) has a dramatic voltage reduction of 2.5 V under the current density of 100 mA/cm2. When compared to the control device, the current efficiency was improved 2.37 times. The maximum brightness increased to 14900 cd/m2 in comparison to that of 5780 cd/m2 for the control device. The performance of the OLED devices was fine-tuned by adjusting the combination of the OPV and OXD units to reach electron-hole balanced conditions. The maximum current efficiency increased to 4.12 cd/A at 5.5 V when the PU layer of OPV: OXD = 67:33 was used. © 2006 American Chemical Society.application/pdf245638 bytesapplication/pdfen-USCondensation; Current density; Light emitting diodes; Polymerization; Synthesis (chemical); Brightness; Current efficiency; Isophorone diisocyanate (IPDI); Voltage reduction; Polyurethanesjournal article10.1021/cm060124w2-s2.0-33748532790WOS:000239758300028http://ntur.lib.ntu.edu.tw/bitstream/246246/87314/1/18.pdf