Micro-mechanical model of TPE made of polypropylene and rubber waste

The aim of this study is to conduct experimental characterization and to develop a micro-mechanical model for thermoplastic elastomers made of polypropylene and particles of rubber waste. Observations by means of Scanning Electron Microscope showed that the elastomer particles have an average dimension of 250 μm and are embedded in a polypropylene matrix. The mechanical behaviour is studied through a series of tensile tests composed of loadings at different strain rates and relaxation steps. The constitutive equations were established within a self-consistent scheme including the mechanical behaviour of the two phases. The matrix is modelled as an elastoviscoplastic solid and the rubber as an elastic solid. Material coefficients have been determined using an inverse method. This paper presents a first version of the micro-mechanical model and a comparison with experimental results.