Physico-chemical observations on polyethylene base resin under the effect of thermal ageing

Within the framework of a project for the better understanding of the behaviour of polyethylene under specific operating conditions, the temperature influence on a polyethylene base resin was studied. A differential scanning calorimetry analysis has shown the effect of annealing on morphological changes. The first was noticed at 318 K while a sharp transition to all amorphous material was observed at around 373 K followed by Fourier transform infrared spectroscopy analysis of the double peak (730-720 cm(-1)), characteristic of crystalline and amorphous states. These observations are used to support tire interpretation of conductivity measurements.