Radiation crosslinking of rubber phase in poly(vinyl chloride)/epoxidized natural rubber blend: Effect on mechanical properties

The effect of pre-irradiation of epoxidized natural rubber (ENR 50) on the properties of 50/50 poly(vinyl chloride)/epoxidized natural rubber blend (PVC/ENR) was investigated. The ENR 50 was irradiated using a 3.0 MeV electron beam accelerator at a dose range of 10-100 kGy in air and at room temperature. The irradiated ENR 50 was then melt blended with PVC using a Brabender Plasticorder Model PL2000 at 50 rpm, 150 °C for 15 min. The effect of electron beam irradiation of the ENR 50 on the 50/50 PVC/ENR blend was studied by examining evidence from the torque-time curve, tensile strength, elongation at break, modulus, hardness, impact strength and gel fraction. The torque-time curves indicated that the irradiation dose has significant influence on the blend homogeneity. An upward tend was observed for tensile strength, modulus, hardness, impact strength and gel fraction of the 50/50 PVC/ENR blend with irradiation dose. Such observation indicate that irradiation of the ENR 50 phase contributes to the enhancement in PVC/ENR blend properties.