Real-time FTIR-ATR spectroscopy to study the kinetics of ultrafast photopolymerization reactions induced by monochromatic UV light

Real-Time FTIR-ATR spectroscopy was used to study the kinetics of photopoly merization reactions induced by monochromatic UV light. Various photoinitia tor systems were tested for their efficiency to start the curing reaction o f acrylates on irradiation at 313 or 222 nm. The effect of physical and che mical factors such as photoinitiator concentration, light intensity, temper ature, monomer functionality and inertization on kinetic parameters like po lymerization rate, induction period and final conversion was studied. The c ontribution of the postcuring to the final conversion was determined by fol lowing the decay of the double bonds during and after irradiation with sing le or multiple short UV flashes with a duration of 50-200 ms. Finally, some investigations of samples from practical applications such as UV-curable p owder coatings, printing inks, and release coatings of silicone acrylates w ill be reported. (C) 1999 Elsevier Science B.V. All rights reserved.