Influence of metal ion on the degradation of LDPE at the composting temperatures

Low Density Polyethylene(LDPE) films with additives that contain metal ions were subjected to accelerated degradation at simulated composting temperatures. The mechanical properties and viscosity-average molecular weight of the samples, during the degradation, were determined and the degradation mechanism was studied. The results show that the samples containing metal ion show considerable decreases. Percentage crystallinity of LDPE in the samples has changed obviously during the degradation. [POOH] increases during the early stage of degradation followed by a more or less flat maximum before it starts to decrease, but carbonyl index shows a polynomial increase during the degradation.