From radical to reversible-deactivation radical polymerization of ethylene

The present paper reviews advancements in reversible-deactivation radical polymerization (RDRP) of ethylene. Polyethylene, one of the most produced polymers, is traditionally made using high-pressure radical polymerization (RP) or catalytic coordination-insertion methods. However, the harsh conditions required for RP and ethylene low reactivity have limited laboratory-scale innovations. Efforts to develop milder polymerization conditions (< 100 degrees C, < 500 bar) have facilitated the exploration of RDRP techniques applied to ethylene. RDRP based on reversible termination or degenerative transfer have been investigated. Among them, those based on degenerative transfer such as reversible addition-fragmentation chain transfer (RAFT), organotellurium mediated radical polymerization (TeRP) or iodine transfer polymerization (ITP) proved more successful, enabling not only controlled homopolymerization of ethylene but also the synthesis of well-defined (block) copolymers based on ethylene.