The Effect of γ-Irradiation on the Structure and Properties of Poly(propylene)/Clay Nanocomposites

The oxidative degradation of PP/OMMT nanocomposites under γ-irradiation was studied. Changes in structure and properties resulting from γ-exposure in the range 0-100 kGy were investigated. The results were analyzed by comparing the influence of PP-g-MA and pristine OMMT on the oxidation kinetics of neat PP. γ-Irradiation in the presence of air strongly degraded the properties of PP materials, particularly for radiation doses above 20 kGy. The rate of oxidative degradation of PP/OMMT/PP-g-MA nanocomposites was much faster than that of neat PP. This suggests that PP-g-MA and pristine OMMT components behave as oxidation catalysts, leading to the formation of free radicals in the polymer matrix.