Comparative study of a variety of ATRP systems with high oxidation state metal catalyst system

MMA (methyl methacrylate) was polymerized in different ATRP systems using the different ligands of HMTETA (1, 1, 4, 7, 10, 10, hexamethyltriethylenetetraamine), TMEDA (N,N,N′,N′-Tetramethylethylenediamine) with copper salts (CuBr/CuBr₂) and EBriB was used as an initiator in toluene at a reaction temperature of 80 °C. Both conventional and a low catalyst to initiator ratios ranging from 1/1 to 0.01/1 were compared in this study. All four of the ATRP methods, such as normal, reverse, AGET and ATRP using a high oxidation state metal complex without any additives, were evaluated at different conditions. The ATRP using a high oxidation state metal system in the absence of a conventional radical initiator like AIBN, which is used in reverse ATRP, or reducing agents such as Sn (EH)₂ in AGET ATRP was a better controlled system in terms of both the catalytic activity and controllability (PDI ∼ 1.2).