Poly(9,9-dialkylfluorene-co-triphenylamine)s - A family of photo-curable hole-transport polymers for polymer light-emitting diodes applications
Journal
European Polymer Journal
Journal Volume
56
Journal Issue
1
Pages
33-44
Date Issued
2014
Author(s)
Abstract
Hole-transporting photocurable blends of (4-(AcOCH2)C 6H4)3N (1) or ((4-(AcOCH2)C 6H4)2NC6H4)2 (2), poly(fluorene-co-triphenylamine)s (PFTs) and diphenyliodonium 9,10-dimethoxyanthracene-2-sulfonate (DIAS, a photoacid generator (PAG)) have been successfully formulated. Under UV irradiation (λ > 200 nm), PAG decomposes to release protons that catalyze the heterolytic decomposition of 1 and 2 to give benzylic cation intermediates. Friedel-Crafts type electrophilic aromatic substitution would then occur at the triphenylamine (TPA) units of PFT, leading to a photo-curing phenomenon. The curing efficiency is therefore highly dependent on the content of TPA in the PFT. This approach can be implemented to PLED applications. Under the optimized conditions, the polymeric light-emitting device of ITO/photo-cross-linkable HTL/PVK-Ir(ppy)3-t-PBD/Mg-Ag, with a turn-on voltage of 9.4 V (1 cd/m2), a maximum brightness of 7630 cd/m2, and a current efficiency of 15.8 cd/A was achieved. The lifetime of the device has also been improved by 1.8 times when compared with that of the STD device. © 2014 Elsevier Ltd. All rights reserved.
SDGs
Type
journal article