Thermal, tensile and rheological properties of linear low density polyethylene (LLDPE) irradiated by gamma-ray in different atmospheres

The aim of this paper is to investigate structural changes of linear low density polyethylene (LLDPE) modified by ionizing radiation (gamma rays) in different atmospheres. The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical–chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. This polymer was irradiated with gamma source of 60Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h. The changes in molecular structure of LLDPE, after gamma irradiations were evaluated using thermogravimetric analyzer (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere.