The effect of polymer chain structure on the optical and electrical properties are reported for poly(4-diphenylaminostyrene) (PDAS), which was prepared by the living anionic polymerization of 4-diphenylaminostyrene (DAS) with the benzyllithium (BzLi)/N,N,N',N'-tetramethylethylenediamine (TMEDA) system The optical properties of PDAS are strongly affected by the stereoregularity of the PDAS polymer chain. intramolecular excimer-forming fluorescence was observed from PDAS with a syndiotactic-rich configuration The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of PDAS were approximately -5 4 and -2 0 eV, respectively, regardless of the polymer chain structure. The hole and electron drift mobilities for PDAS were in the order of 10(-4) to 10(-5) (cm(2)/V s) and 10(-5) (cm(2)/V s), respectively, with negative slopes. The distance of each triphenylamino (TPA) group in the polymer chain was a major factor influencing the drift mobility of PDAS The current-voltage (I-V) characteristics of PDAS were controllable according to the polymer chain structure of PDAS. (C) 2010 Elsevier Ltd. All rights reserved