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In Atom Transfer Radical Polymerization (ATRP), Cu 0 acts as a supplemental activator and reducing agent (SARA ATRP) by activating alkyl halides and (re)generating the Cu I activator through a comproportionation reaction, respectively. Cu 0 is also an unexplored, exciting metal that can act as a cathode in electrochemically mediated ATRP ( e ATRP). Contrary to conventional inert electrodes, a Cu cathode can trigger a dual catalyst regeneration, simultaneously driven by electrochemistry and comproportionation, if a free ligand is present in solution. The dual regeneration explored herein allowed for introducing the concept of pulsed galvanostatic electrolysis (PGE) in e ATRP. During a PGE, the process alternates between a period of constant current electrolysis and a period with no applied current in which polymerization continues via SARA ATRP. The introduction of no electrolysis periods without compromising the overall polymerization rate and control is very attractive, if large current densities are needed. Moreover, it permits a drastic charge saving, which is of unique value for a future scale-up, as electrochemistry coupled to SARA ATRP saves energy, and shortens the equipment usage. 

The stringent control over the polymerization of less activated monomers remains one major challenge for Reversible Deactivation Radical Polymerizations (RDRP), including Atom Transfer Radical Polymerization (ATRP). Electrochemically mediated ATRP ( e ATRP) of a gaseous monomer, vinyl chloride (VC), was successfully achieved for the first time using a stainless-steel 304 (SS304) electrochemical reactor equipped with a simplified electrochemical setup. Controlled polymerizations were confirmed by the good agreement between theoretical and measured molecular weights, as well as the relatively narrow molecular weight distributions. Preservation of chain-end fidelity was verified by chain extension experiments, yielding poly(vinyl chloride) (PVC) homopolymers, block and statistical copolymers. The possibility of synthesizing PVC by e ATRP is a promising alternative to afford cleaner (co)polymers, with low catalyst concentration. The metal body of the reactor was also successfully used as a cathode. The setup proposed in this contribution opens an avenue for the polymerization of other gaseous monomers.