Influence of different antioxidants on cure kinetics and aging behaviours of ethylene propylene diene rubber/low density polyethylene blends

The aim of this article is to study the effect of antioxidants on cure properties and aging behaviour of ethylene propylene diene rubber (EPDM) and EPDM/low density polyethylene (LDPE) blends. Dicumyl peroxide cured EPDM and EPDM/LDPE blends are prepared with three categories of antioxidants, including: amine, N-isopropyl-N-phenyl-ρ-phenylenedia mine (antioxidant 4010NA) and 2,2,4-trimethyl-1,2-dihydroquinoline (antioxidant RD); phenol, η-Otadecyl-β-(4-hydroxy-3,5-ditert-butyl-phenyl)-propionate (antioxidant 1076) and sulphur containing antioxidant, 2-mercapto benzimidazole (antioxidant MB). The damp heat aging was carried out at a relative humidity of 93% and a temperature of 40°C. The thermal aging was performed at 120°C. The two types of aging have been taken for eight weeks respectively. The combined antioxidant RD/MB is a favourable additive. The cure characteristics of EPDM with antioxidant RD/MB are notable compared with those of EPDM without antioxidants. Additionally, antioxidant RD/MB has the sound aging performance for the EPDM and EPDM/LDPE blend. Antioxidant 4010NA performs poorer than others during aging, due to the remarkable retardation for the peroxide vulcanisation process.