Synthesis of well-defined ethylene-based copolymers: on track using organometallic-mediated radical polymerization

Organometallic-Mediated Radical Polymerization (OMRP)1 has received renewed interest in recent years since proving its efficiency for non-activated monomers like vinylacetate (VAc), N-vinylamides, etc. Nevertheless, important mechanistic questions and challenges remained. A major goal in the field of controlled radical polymerization today consists in the design of well-defined ethylene containing (co)polymers. A recent mechanistic study on the impact of head-to-head addition on the course of the VAc polymerization by OMRP provided a strong incentive to evaluate the copolymerization of VAc with ethylene by this technique. Indeed, the latter revealed that dormant chains resulting from inverted head-to-head additions in the VAc polymerization, which mimics a terminal ethylene-cobalt moiety, reactivates at a similar rate compared to the ones resulting from the regular head-to-tail addition. As a result, well-defined statistical and block-like ethylene-based copolymers were prepared. These achievements represent an important step towards a versatile synthetic platform for polyolefine-based materials.