The synthesis of macromonomers of acrylic acid was performed by telomerization in a three-step process. The first step was the telomerization of tert-butyl acrylate in the presence of thioglycolic acid. Different molecular weights were obtained with different ratios of the monomer to the transfer agent. Good control of the molecular weights and architectures of the oligomers (e.g., the presence of an acid function on the chain end) was observed. The transfer constant of tert-butyl acrylate with thioglycolic acid was assessed (chain-transfer constant = 0.6). In the second step, the terminal unsaturation of the oligomers was obtained by the reaction of the terminal acid groups with 2-isocyanatoethyl methacrylate to yield the macromonomers of tert-butyl acrylate. In the last step, the tert-butyl acrylate groups were hydrolyzed in the presence of trifluoroacetic acid at room temperature. The macromonomers were copolymerized with styrene to obtain graft copolymers, and the reactivity ratios were evaluated. Finally, the copolymers were characterized with surface electron microscopy and atom force microscopy. (c) 2006 Wiley Periodicals, Inc.