End-functional polystyrenes via quasiliving atom transfer radical polymerization and new polymer structures therefrom

Polystyrenes with 2-chloro-2-phenylethyl chain end (PSt-Cl) prepared by quasiliving atom transfer radical polymerization (ATRP) are useful intermediates for the synthesis of a variety of well-defined macromolecular architectures. The preparation of star-shaped polystyrenes by quasiliving ATRP of divinylbenzene initiated by PSt-Cl and hyperbranched polystyrene by self-grafting of PSt-Cl mediated with TiCl, is carried out in the course of our studies. Allyl-terminated macromonomers were also prepared by reacting PSt-Cl with allyltrimethylsilane in the presence of TiCl4. This PSt-allyl was copolymerized with propylene by metallocene catalysts yielding novel poly(propylene-g-styrene) (PP-g-PSt) graft copolymers.