A self-condensing monomer 4-(4'-bromophenyl)-4"-n-butyldiphenylamine (1) was synthesized, and successfully converted to poly(4-n-butyltriphenylamine) (PBTPA) by arylamination using palladium catalyst. PBTPAs can be functionalized at both terminals separately by adding an aryl bromide or arylamine derivatives as a terminator, which enabled us to prepare the diblock copolymer PBTPA-block-PEO. Polymer characterization was performed by H-1 NMR, C-13 NMR, and DSC, which confirmed that the PEO segment was successfully introduced at the terminal of PBTPA. The surface morphology in a thin film of PBTPA-block-PEO was examined by AFM, revealing that a micro phase-separated structure or cup-shaped structure with PEO sphere domains formed when the film was spin-cast from 1,1,2,2-tetrachloroethane solutions of different concentrations. (C) 2008 Elsevier Ltd. All rights reserved.