Synthesis of aromatic carboxyl functionalized polymers by atom transfer radical polymerization

The synthesis of aromatic carboxyl functionalized polymers by atom transfer radical polymerization is described. The alpha -bromo-p-toluic acid (1) in itiated polymerization of styrene in the presence of copper(I) bromide and 2,2'-bipyridyl affords quantitative yields of the corresponding aromatic ca rboxyl functionalized polystyrene (2). Polymerization proceeded via a contr olled free radical process to afford quantitative yields of the correspondi ng aromatic carboxyl functionalized polymers with predictable molecular wei ghts (M-n=1600-25 900 g mol(-1)), narrow molecular weight distribution (M-w /M-n = 1.1-1.40) and an initiator efficiency above 0.87. The polymerization process was monitored by gas chromatographic analysis. The functionalized polymers were characterized by thin layer chromatography, size exclusion ch romatography, spectroscopy, potentiometry and elemental analysis. (C) 2000 Society of Chemical Industry.