Direct Observation of Acrylate Radicals: A New Acces to their Reactivity

The acrylate radicals produced by addition of aminoalkyl radicals to an acrylate unit have been directly observed by transient absorption spectroscopy. These acrylate radicals are characterized by a strong absorption in the visible part of the spectrum allowing an easy study of their chemical reactivity. Therefore, a new method for the determination of both the addition and recombination rate constants is proposed. These radicals being particularly important as possible representative of propagating radicals, this approach appears powerful and promising to study the reactivity of different monomers and to determine both propagation and termination rate constants of radical polymerization.