Journal of Polymer Science Part A: Polymer Chemistry, Vol.50, No.18, 3875-3884, 2012
Solution-processable and thermally cross-linkable fluorene-cored triple-triphenylamines with terminal vinyl groups to enhance electroluminescence of MEH-PPV: Synthesis, curing, and optoelectronic properties
This study reports the synthesis, curing, and optoelectronic properties of a solution-processable, thermally cross-linkable electron- and hole-blocking material containing fluorene-core and three periphery N-phenyl-N-(4-vinylphenyl)benzeneamine (FTV). The FTV exhibited good thermal stability with Td above 478 degrees C in nitrogen atmosphere. The FTV is readily cross-linked via terminal vinyl groups by heating at 160 degrees C for 30 min to obtain homogeneous film with excellent solvent resistance. Multilayer PLED device [ITO/PEDOT:PSS/cured-FTV/MEH-PPV/Ca (50 nm)/Al (100 nm)] was successfully fabricated using solution processed. Inserting cured-FTV is between PEDOT:PSS and MEH-PPV results in simultaneous reduction in hole injection from PEDOT:PSS to MEH-PPV and blocking in electron transport from MEH-PPV to anode. The maximum luminance and maximum current efficiency were enhanced from 1810 and 0.27 to 4640 cd/m2 and 1.08 cd/A, respectively, after inserting cured-FTV layer. Current results demonstrate that the thermally cross-linkable FTV enhances not only device efficiency but also film homogeneity after thermal curing. FTV is a promising electron- and hole-blocking material applicable for the fabrication of multilayer PLEDs based on PPV derivatives. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 000: 000000, 2012