Abstract: A new approach to the synthesis of dendrimer-like star polymer, [(PMMA)₂PSt]₄, was presented via the combination of atom transfer radical polymerization(ATRP) and ckick chemistry. Firstly four-arm bromine-terminated polystyrene(PSt-Br)₄ was obtained from ATRP of styrene using pentaerythritol tetra(2-bromoisobutyrate) as an initiator, and the (PSt-Br)₄ was efficiently converted to the azido-terminated polymers[(PSt-N₃)₄] through the bromine substitution reaction with sodium azide. Furthermore, the(PSt-N₃)₄ reacted with propargyl 2,2-bis[2-(bromomethyl)propionato]propionyrate via a click reaction, 1,3-dipolar cycloaddition reaction, and the polymer[(PSt-Br₂)₄] containing eight end-bromine was obtained. The (PSt-Br₂)₄ could further serve as a macroinitiator for the ATRP of methyl methacrylate(MMA). Accordingly, the dendrimer-like star polymer, [(PMMA)₂PSt]₄ was successfully prepared. The structure of [(PMMA)₂PSt]₄ was characterized via IR, ¹H NMR, GPC and DSC.

Key words: Atomic transfer radical polymerization(ATRP), Click chemistry, Dendrimer-like star polymer