Influence of electron beam irradiation on PP/clay nano-composites prepared by melt blending

In this research, the melt blending technique was used to prepare various polypropylene (PP) based nanocomposites. A commercial organoclay (denoted 15A) served as the filler for PP matrix, and the maleic anhydride modified PP was used as compatibilizer. The specimens were subjected to electron beam (EB) irradiation. The purpose of the study focuses on the influences of EB irradiation on the thermal stability and mechanical properties of the nanocomposites. The morphology of the nanocomposites was studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD and SEM results showed that these nanocomposites are best described as intercalated systems. PP/Clay nanocomposites showed good thermal stability in the TGA analysis. TGA data at 500KGy showed that the EB irradiation has negative effect on thermal stability of the nanocomposites. Mechanical testing showed that the EB irradiation strongly influences the mechanical properties (tensile strength, Young's modulus and hardness) of PP/Clay nanocomposites. The value of tensile strength decreases remarkably for all specimens with increasing irradiation dose up to about 550 KGy, but this reduction for nanocomposites with 3% clay is less than that of the pure PP/PP-g-MA blend. In higher irradiation doses, reduction in tensile strength of PP nanocomposites is less than that of the pure PP/PP-g-MA blend. Optimum irradiation dose of Young's modulus for PP/Clay nanocomposites with 5% clay is 450 KGy. The hardness of the nanocomposites with 5% clay was found to decrease with increase in irradiation dose. Keywords: Polypropylene (PP); Nanocomposites; Organoclay; Electron beam irradiation; Compatibilizer; Thermal stability.