Kinetics of Photo-Induced Chemiluminescence Decay from Polymers

Previous studies showed that the decay of photo-induced chemiluminescence (PICL) in polymers does not obey classical first or second order kinetics. This study demonstrates that plotting PICL second-order decay from three fibrous polymers (polypropylene, polyamide 6 and wool keratin) in a modified form gives excellent linear plots. The existence of a significantly less reactive fraction of macroperoxy radicals in heterogeneous polymers can explain the deviation from classical behaviour and this fraction can be quantified from the gradient of the modified plots. This unreactive fraction could be due to either dispersive or diffusive effects in a disordered heterogeneous polymer medium. Both dispersive and diffusive models give very good fits to the PICL decay profiles using three fitting parameters.