Synthesis of poly(2-hydroxyethyl methacrylate) in protic media through atom transfer radical polymerization using activators generated by electron transfer

Atom transfer radical polymerization (ATRP) using activators generated by electron transfer (AGET) was investigated for the controlled polymerization of 2-hydroxyethyl methacrylate (HEMA) in a protic solvent, a 3/2 (v/v) mixture of methyl ethyl ketone and methanol. The AGET process enabled ATRP to be started with an air-stable Cu(II) complex that was reduced in situ by tin(II) 2-ethylhexanoate. The reaction temperature, Cu catalysts with different ligands, and variation of the initial concentration ratio of HEMA to the initiator were examined for the synthesis of well-controlled poly(2-hydroxyethyl methacrylate) and a poly(methyl methacrylate)-b-poly(2-hydroxyethyl methacrylate) block copolymer. The level of control in AGET ATRP was similar to that in normal ATRP in protic solvents, and this resulted in a linear increase in the molecular weight with the conversion and a narrow molecular weight distribution (weight-average molecular weight/number-average molecular weight < 1.3). (c) 2006 Wiley Periodicals, Inc.