Chemiluminescence studies on comparison of antioxidant effectiveness on multiextruded polyethylenes

Several polyethylene resins; high density polyethylene (Ph-HDPE, Phillips metal oxide catalyst) and linear low density polyethytlenes (LLDPE, formed using Ziegler-Natta catalyst and metallocene catalyst technology, m-LLDPE) were used in order to acquire an insight in to the effect of different polymerization catalyst systems on the melt stabilization performance of single AO. Chemiluminescence (CL) and melt flow rate (MFR) were used to analyze the degradation as a function of the number of passes through a twin-screw extruder. A good correlation was obtained, and the additives resulting with the best melt flow stability in the polymer were the same as those that promote the best CL results.