Mechanical and thermal properties of gamma-ray irradiated polyethylene blends

Abstract

In this work, the results obtained by gamma-ray irradiation of polyethylene (PE) blends are presented. The blends were produced by injection molding at 220°C with different compositional ratios, i.e. 100/0, 15/85, 25/75, 50/50/, 75/25, 85/15, and 0/100, of low-density PE with high-density PE and linear low-density PE. The exposure of these blends to different doses of 60Co gamma radiation up to 1500kGy improves the mechanical properties due to partial cross-linking. Diffraction scanning calorimetry, infrared spectroscopy and scanning electron microscopy have been used to investigate the effect of gamma irradiation on the thermal behavior of the polymer material. After the radiation treatment, the melting peak of the low-density PE component decreases in intensity as the absorbed dose increases. On the contrary, melting peak of the high-density component increases in intensity and shifts to lower temperatures as the absorbed dose increases. The correlation between the mechanical properties and the morphology of the blends is discussed.