Enhancement of PVC/ENR blend properties by electron beam irradiation: effect of stabilizer content and mixing time

The irradiation-induced enhancement of 50/50 PVC/ENR blend was investigated with particular attention to PVC phase stabilization and Brabender mixing time. The blends which were prepared with the addition of 1-5 phr tribasic lead sulfate (TBLS) at 6 and 30 min mixing time were irradiated using a 3.0 MeV electron accelerator with doses ranging from 0 to 200 kGy. The effect of TBLS content and mixing time were studied by examining evidence from Bra bender torque-time curves, tensile strength, elongation at break, modulus a t 100% elongation and tan delta curves. Addition of 2 phr TBLS was found to render optimum tensile properties upon irradiation. The higher tensile pro perties observed for the blend obtained at 30 min mixing time reflect the i mportance of blend homogeneity in enhancing the irradiation-induced crossli nking. The decrease in blend heterogeneity with mixing time was evident fro m tan delta curves. (C) 2001 Elsevier Science Ltd. All rights reserved.