Processing and properties of thermoplastics elastomers based on recycled polyethylene and EPDM

Abstract

In order to reduce raw material costs, thermoplastic elastomer (TPE) resins were produced using recycled materials. In particular, post-consumer polyethylene (PE) and ethylene-propylene diene monomer (EPDM) were used. Nevertheless, a coupling agent based on maleated polyethylene (MAPE) was used to determine if interfacial properties can be modified. The compounds were processed via twin-screw extrusion and then pelletized. The samples were finally produced by compression molding with different EPDM (0, 40, 50, 60, 80, 90%) and MAPE (0, 5, 10 phr) contents giving a wide range of properties. Based on the samples produced, a complete mechanical characterization in terms of tensile, torsion, and flexural properties was performed, as well as morphology, density and hardness. The results show that the effect of coupling agent addition is only important at high EPDM contents with a transition concentration around 60% where a balance between rigidity, elasticity and strength can be obtained.