Generation and reactivity of a lactone derived radical

The behavior of a lactone derived acrylate monomer (LacA) representative of Highly Reactive Acrylate Monomers (HRAM) is studied. Time resolved absorption spectroscopy allows the direct detection of the lactone derived radical Lac. This radical exhibit an unusual reactivity: Lac is almost not sensitive to oxygen (rate constant <5 × 106 M−1 s−1).