Mechanistic aspects of 'living' free radical polymerization and initiation mediated by nitroxides

Polymers such as polystyrene, prepared in the presence of nitroxides such as TEMPO, behave as living or dormant polymers, capable of undergoing further polymer growth at temperatures (e.g. 120°C) under which the nitroxide cap can readily come off. This methodology is the subject of much current attention since it allows low polydispersity polymers to be prepared under conditions of free radical polymerization. Our studies have centered on the synthesis of novel initiators; mechanism of living free radical polymerization; possible role of acids; initiation by nitroxides; thermodynamics of bond cleavage; and possible photoinduced routes to living free radical polymerization. Laser techniques have proven very useful in the study of some of these processes.