Newly designed star-shaped polystyrene: Synthesis and characterization

In this study, emphasis is placed on the synthesis of hexaarm star polystyrene obtained via "living" cationic polymerization, using a newly designed hexafunctional initiator (1). This hexafunctional initiator (1) has been prepared via [Fe(C5H5)](+)-induced hexabenzylation of hexamethylbenzene, followed by a regiospecific sequence of reactions meant to generate six phenylethyl chloride (PhEtCl) groups on the para position of the outer rings. The conditions that afford a truly controlled polymerization of styrene were first defined using PhEtCl as the monofunctional model of (1). Finally, these conditions were used to build hexaarm star polymers from (1) as plurifunctional initiator. Well-defined star samples were obtained over a wide range of molar masses (10(3) g/mol less than or equal to M-n less than or equal to 10(5) g/mol) via this original divergent method.