Eutectic Mixtures as a Green Alternative for Efficient Catalyst Recycling in Atom Transfer Radical Polymerizations

A new solvent mixture, based on ethanol/reline (EM: eutectic mixture), was investigated for the supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) of methyl acrylate (MA) near room temperature, for the first time, affording complete catalyst recovery and reuse. The kinetic results revealed that the polymerizations were controlled, with polymers having narrow molecular weight distributions (D < 1.2). The living character of the resultant PMA was confirmed by the synthesis of a well-defined PMA-b-PBA block copolymer. Remarkably, it was demonstrated that the Cu(0)/CuBr2/Me6TREN (Me6TREN: tris[2-(dimethylamino) ethyl] amine) could be recovered from the final reaction mixture and reused for new successful SARA ATRP of MA, suggesting that the reported system could be very attractive from both the economic and environmental perspectives. (C) 2016 Wiley Periodicals, Inc.