Sequential Double Polymer Click Reactions for the Preparation of Regular Graft Copolymers

Abstract

In this study, graft copolymers with regular graft points containing polystyrene (PS) backbone and poly(methyl methacrylate) (PMMA), poly(tert-butyl acrylate) (PtBA), or poly (ethylene glycol) (PEG) side chains were simply achieved by a sequential double polymer click reactions. The linear alpha-alkyne-omega-azide PS with an anthracene pendant unit per chain was produced via atom transfer radical polymerization of styrene initiated by anthracen-9-ylmethyl 2-((2-bromo-2-methylpropanoyloxy)methyl)-2-methyl-3-oxo-3-(prop-2-ynyloxy) propyl succinate. Subsequently, the azide-alkyne click coupling of this PS to create the linear multiblock PS chain with pendant anthracene sites per PS block, followed by Die Is-Alder click reaction with maleimide end-functionalized PMMA, PtBA, or PEG yielded final PS-g-PMMA, PS-g-PtBA or PS-g-PEG copolymers with regular grafts, respectively. Well-defined polymers were characterized by H-1 NMR, gel permeation chromatography (GPC) and triple detection GPC. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 1195-1200,2011