Polyfluorene-Polytriarylamine Block Copolymer as an Additive for Electroluminescent Devices Based on Polymer Blends

Mehdi Jahanfar, Ying Tan, Kousuke Tsuchiya, Takeshi Shimomura, Kenji Ogino

Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.

DOI: 10.4236/ojopm.2013.32007                

Abstract

Electroluminescent characteristics were investigated for the blue emitting devices fabricated with the blend systems consisting of hole transporting polytriarylamine (PTAA), electron transporting polyfluorene (PF), and a block copolymer with both segments (PF-b-PTAA) as an active layer in order to elucidate the relationship between the chemical nature and morphology of the active layer, and EL performance. The addition of PF-b-PTAA to PF homopolymer afforded the hole injecting and/or electron blocking ability to increase the efficiency. The addition to PF/PTAA blend keeping the chemical composition constant also improved the performance by controlling the morphology and/or the domain size in phase-separated films.

Keywords

Polyfluorene; Polytriarylamine; Block Copolymer; Polymer Blend; Polymer-Light Emitting Diode

Conflicts of Interest

The authors declare no conflicts of interest.

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