Electro‐Controlled Living Cationic Polymerization

Cationic polymerizations have long been industrialized; however, stimulus‐regulated cationic polymerization remains to be developed. An electrochemically controlled living cationic polymerization is presented for the first time. In the presence of external potential and organic‐based electrocatalyst, a series of monomers can be polymerized under a cationic chain‐transfer mechanism. The resulting polymers exhibit well‐defined molecular mass, narrow dispersity, and good chain‐end fidelity. By controlling the external potential to switch the electrocatalyst between its oxidized and reduced states, ON/OFF polymerization can be achieved. This method is a versatile way to a large range of monomers, including vinyl ether‐type and p‐substituted styrene‐type monomers. Given the sustainability feature and broad interest of electrochemical synthetic techniques, we envisaged that this method would lead a new direction of external regulated living ionic polymerization.