Controlling reversible complexation-mediated polymerization (RCMP) via deep eutectic solvents: fast kinetics, narrow molecular weight distribution and mechanistic insights

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric materials. In this work, serials of deep eutectic solvents (DES) with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization (RCMP) for the first time, yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil systems. The mechanism and elementary reaction of RCMP were explored deeply, revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization rate. Moreover, the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic capacity. This investigation demonstrated the considerable potential of DES for RCMP, which is anticipated for other polymerization applications as a novel medium mode.