Reverse atom transfer radical polymerization of methyl methacrylate in room‐temperature ionic liquids

The reverse atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was successfully carried out in 1‐butyl‐3‐methylimidazolium hexafluorophosphate with 2,2′‐azobisisobutyronitrile/CuCl2/bipyridine as the initiating system, which had been reported as not able to promote a controlled process of MMA in bulk. The living nature of the polymerization was confirmed by kinetic studies, end‐group analysis, chain extension, and block copolymerization results. The polydispersity of the polymer obtained was quite narrow, with a weight‐average molecular weight/number‐average molecular weight ratio of less than 1.2. In comparison with other reverse ATRPs in bulk or conventional solvents, a much smaller amount of the catalyst was used. After a relatively easy removal of the polymer and residue monomer, the ionic liquid and catalytic system could be reused without further treatment.