Effects of ionizing radiation on the molecular structure of polyethylene

Abstract

This study investigates the effects of gamma irradiation (60Co) at doses of 100 and 300 kGy on HDPE composites reinforced with 17 wt% glass fiber. The aim is to evaluate structural and thermal modifications induced by irradiation for potential use in high-demand industrial environments. Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Heat Deflection Temperature (HDT), Vicat Softening Temperature, X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) were employed to characterize changes in the material. Results showed slight decreases in melting temperature and minor changes in crystallinity. However, improvements were observed in HDT and Vicat values, indicating enhanced thermal resistance. SEM images revealed good fiber dispersion and fracture surface morphology, although signs of interfacial incompatibility were still present. These findings support the application of gamma-irradiated HDPE composites in conditions involving thermal and mechanical stress.