Mechanical properties of recycled LDPE/EVA/ground tyre rubber blends: Effects of EVA content and postirradiation

Abstract

AbstractThermoplastic elastomers were prepared from recycled low density polyethylene [rLDPE] and virgin low density polyethylene (LDPE), respectively, ground tyre rubber (GTR), and ethylene vinyl acetate (EVA) copolymer. The amounts of the rLDPE and GTR were fixed at 40 and 30 wt %, respectively, in the formulations, whereas the LDPE and EVA contents varied each between 0 and 30 wt %. The fresh LDPE served for reduction of the melt viscosity and EVA was used for improving the elastomeric properties. Blends of different compositions (by varying the LDPE/EVA ratio) were produced by twin‐screw extrusion and pelletized. Specimens were produced by injection molding and subjected to tensile and instrumented falling weight impact (IFWI) tests. To improve the mechanical performance of the blends, the injection molded specimens were electron beam irradiated at 150 kGy absorbed dose. Static tensile and hysteresis, IFWI and dynamic mechanical thermal analysis tests were performed on the specimens and the fracture surface was inspected with a scanning electron microscope. The results indicated that better rubber‐like properties were achieved with increasing EVA content. Moreover, postirradiation proved to be very beneficial, especially for blends containing relative high amounts of EVA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012