Synthesis of polystyrene-block-poly (butyl acrylate) copolymers using nitroxide-mediated living radical polymerization in miniemulsion

Communication: Living free-radical butyl acrylate polymerization in miniemu lsion was initiated by polystyrene bearing a nitroxyl end group to yield po lystyrene-block-poly(butyl acrylate) block copolymers. Polystyrene macroini tiator was obtained using different initiating systems (potassium persulfat e or benzoyl peroxide) in the presence of 2,2,6,6-tetramethylpiperidine-N-o xyl (TEMPO) or the more water-soluble 4-hydroxy-2,2,6, 6-tetramethylpiperid in-N-oxyl (OH-TEMPO). The nitroxide water-solubility has an important influ ence in determining molecular weight distributions and controlling the grow th of the second block.