The use of iodocompounds in radical polymerization presents a straightforward way to prepare controlled macromolecular architectures. Herein, ab initio emulsion polymerization of styrene has been successfully performed by iodine transfer polymerization using methyl-2-iodopropionate as transfer agent, 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] tetrahydrate (VA-057) as initiator and dodecyl sulfate sodium salt (SDS) as surfactant, yielding stable and uncoloured latexes (e. g. styrene conversion = 76%, M-n,M- theoretical = 7800 g mol(-1), M-n,M-SEC = 8400 g mol(-1), M-w/M-n = 1.84, particle diameter d(p) = 55 nm with a monomodal particle size distribution). Hence, the molecular weight of the polymer chains could be accurately controlled by the concentration of transfer agent. Furthermore, a poly(styrene)- b-poly(styrene-co-butyl acrylate) block copolymer latex was synthesized in seeded emulsion polymerization, proving the living character of the polymerization. (C) 2016 Elsevier Ltd. All rights reserved.