The effect of polyhedral oligomeric silsesquioxanes (POSSs) incorporation in ethylene-propylene-dieneterpolymer (EPDM): a thermal study

A series of ethylene-propylene-diene-terpolymer (EPDM)/polyhedral oligomeric silsesquioxane (POSS) composites at different percentage of POSS were prepared and subjected to γ-irradiation. Both irradiated and non-irradiated EPDM and composites were investigated by the means of thermal analysis to verify if the presence of POSS molecules is able to reduce the oxidation level of free radicals generated during the degradation and to evaluate the efects of the irradiation. EPDM composites at 1, 3 and 5% wt of POSS were thus degraded in a thermogravimetric (TG) balance in dynamic heating conditions (25–700 °C), in both inert and oxidative atmosphere by lowing nitrogen and air respectively. Thermal characterization was then completed by carrying out Diferential Scanning Calorimetry (DSC) analysis from sub-ambient to better highlight the melting of the polymer and polymer composites occurring just above the room temperature. FTIR spectroscopy was also performed for the prepared samples to check the presence of the molecular iller in the composites and for the TG’s residue at 700 °C, in order to evaluate its nature. DSC and TGA parameters were detected and discussed to have information about the efect of the degradation’s environment, the efect of irradiation on polymer stabilization and the efect of POSS content in the polymer matrix.