Propagating Radicals in Photo-Initiated Polymerization as Detected by Time-Resolved CWand FT-ESR Spectroscopy

The primary propagating radicals in photo-initiated polymerization of isoprene and MMA were directly detected and assigned for the first time by use of time-resolved ESR spectroscopy. Based on the kinetic analysis including the spinlattice relaxation, the rate constant of the formation and the relaxation time were determined for the primary propagating radicals by simulating time- profile of the FT-ESR intensity.