The contribution of BaTiO3 to the stability improvement of ethylene-propylene-diene rubber. Part III. – Comparative assay: EPDM vs EPR

Abstract

This study presents the functional effects of doped BaTiO3 powders loaded in ethylene-propylene elastomers (copolymer – EPR and terpolymer – EPDM) investigated by chemiluminescence (CL). The presence of foreign atoms (lanthanum and cerium) in the barium titanate lattice produces an improved activity on the stabilization of polymer matrices. The concentration of filler was 1 wt%, where the doping atoms behave as the trapping radicals assuring the increase of the low onset oxidation temperatures for pristine material (168 °C for EPDM and 175 °C for EPR) to higher values for BaTiO3/La (183 °C for EPDM and 189 °C for EPR) and BaTiO3/La (190 °C for EPDM and 195 °C for EPR) after receiving 25 kGy. The isothermal determinations point out the protection efficiency proved by the lower positions of the recorded CL spectra for composites in respect with pristine polymers. The compared protection activities at 100 kGy exhibited by the studied composites highlight the greater contribution of BaTiO3/Ce than BaTiO3/La indicating the dependence of stabilization effectiveness on the nature of dopant. The present results state the structural influence of backbone configuration on the filler effects on the amelioration of thermal and radiation strengths.