Star polymers by photoinduced copper-catalyzed azide-alkyne cycloaddition click chemistry

Well-defined star polymers consisting of tri-, tetra-, or octa-arms have been prepared via coupling-onto strategy using photoinduced copper(I)-catalyzed 1,3-dipolar cycloaddition click reaction. An azide end-functionalized polystyrene and poly(methyl methacrylate), and an alkyne end-functionalized poly(epsilon-caprolactone) as the integrating arms of the star polymers are prepared by the combination of controlled polymerization and nucleophilic substitution reactions; whereas, multifunctional cores containing either azide or alkyne functionalities were synthesized in quantitatively via etherification and ring-opening reactions. By using photoinduced copper-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction, reactive linear polymers are simply attached onto multifunctional cores to form corresponding star polymers via coupling-onto methodology. The chromatographic, spectroscopic, and thermal analyses have clearly demonstrated that successful star formations can be obtained via photoinduced CuAAC click reaction. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1687-1695