Facile synthesis of block copolymers from a cinnamate derivative by combination of AGET ATRP and click chemistry

Abstract

An azido- and bromo-containing compound derived from naturally occurring ethyl cinnamate was used successfully to prepare block copolymers by a combination of ‘activator generated by electron transfer atom transfer radical polymerization’ (AGET ATRP) and Huisgen “click” reactions in emulsion. First, azido-end poly(methyl methacrylate) and alkyne-end polystyrene were prepared under AGET ATRP conditions, then, poly(methyl methacrylate) block polystyrene (PMMA-b-PS) diblock copolymer was formed by Huisgen 1,3-dipolar cycloaddition. Finally, polystyrene block poly(methyl methacrylate) block polystyrene (PS-b-PMMA-b-PS) triblock copolymer was synthesized via simultaneous AGET ATRP and click reactions, catalyzed by the same copper-based catalyst. The polymers were characterized by 1H nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC), which confirmed the successful synthesis of the corresponding polymers.