Copper Removal in Atom Transfer Radical Polymerization through Electrodeposition

We describe the removal of copper from atom transfer radical polymerization (ATRP) through electrochemistry. tert‐Butyl methacrylate ATRP initiated by a PEO macroinitiator was run with CuBr complexed by N‐alkyl‐2‐pyridylmethanimine (Schiff base) or 2,2′‐bipyridyl (bpy) as catalyst. Voltammetry experiments using a CuBr/(Schiff base N‐morpholine‐2‐pyridylmethanimine)2 complex on a Pt electrode shows an oxidation peak of the ligand at 1.2 V permitting the oxidative destruction of the complex and so the elimination of copper. Using a Hg electrode, it is possible to directly reduce these complexes (at −2.1 V for the morpholine‐2‐pyridylmethanimine, −2.19 V for the butyl‐2‐pyridylmethanimine, and −2.25 V for the bpy). This complex reduction, followed by the formation of a copper amalgam, leads to the quantitative removal of copper and proceeds without polymer degradation. The electrochemical removal of copper from the ATRP reaction.