An all Atom Transfer Radical Polymerization (ATRP) route to synthesize miktoarm ABC star terpolymer, mu-(poly(methyl methacrylate)-poly(ethylene oxide)-polystyrene) (mu-(PMMA-PEO-PS)), was demonstrated. Poly(methyl methacrylate) (PMMA) with a halide end group was first prepared by ATRP of MMA. It was then activated under ATRP conditions at 30 degrees C to add a styrenic-terminated PEO macromonomer, resulting in the formation of PMMA-b-PEO. Finally, the active halide at the junction point of the diblock copolymer was used to initiate the ATRP of St at higher temperature. By a similar approach, mu-(poly (phenyl methacrylate)-poly(ethylene oxide)-polystyrene) (mu-(PhMA-PEO-PS)) was synthesized, hydrolysis of which in basic medium gave mu-(PMAA-PEO-PS). The polymers were characterized by H-1 NMR spectroscopy and gel permeation chromatography. (C) 2008 Elsevier Ltd. All rights reserved.