Chemiluminescence study of commercial type-B gelatines

The chemiluminescence emission of type-B commercial gelatines films was studied under different conditions. The influence of the gel strength resistance or bloom value of the gelatines on the characteristics of the emission has been investigated. Gelatine material of better quality, bloom 225, gives lower emission than the bloom 75 gelatine material under all the conditions employed in this work. The level of hydroperoxide concentration, determined in the gelatine films, correlates with the emission intensity. A mechanism of hydroperoxide and peroxide radical formation has been proposed in a similar way to that of the autooxidation reactions that take place on N-alkyl amide products. The emission is enhanced drastically in the presence of oxygen and at temperatures above the Tg of the gelatine materials. This fact confirms the important role of oxygen mobility in the material. Also, at temperatures higher than Tg the disproportionation reaction between peroxide radicals, responsible of the emission, is favoured.