AGET ATRP in the presence of air in miniemulsion and in bulk

The recently developed initiation system, activators generated by electron transfer (AGET), is used in atom transfer radical polymerization (ATRP) in the presence of a limited amount of air. Ascorbic acid and tin(II) 2-ethylhexanoate are used as reducing agents in mimemulsion and bulk, respectively. An excess of reducing agent consumes the oxygen present in the system and, therefore, provides a deoxygenated environment for ATRP. ATRP of butyl acrylate is successfully carried out in miniemulsion and in the presence of air. During polymerization the radical concentration remains constant. The polymerization reaches over 60% monomer conversion after 6 h, which results in polymers with a predetermined molecular weight (M) over bar (n) = 14 000 g . mol(-1) and a low polydispersity ((M) over bar (w)/(M) over bar (n) = 1.23). AGET ATRP of styrene is also successful in bulk in the presence of air, as evidenced by linear semi-logarithmic kinetics, which leads to polystyrene with an (W) over bar (n) of 13 400 mol(-1) and a low polydispersity index ((M) over bar (w)/(M) over bar (n) = 1.14).