In current polymer postconsumer waste streams, more and more incompatible blends are found which are nowadays non valorized. Already some companies are applying compatibilizers to increase the value of these kind of waste streams; sometimes upcycling is used to describe this process. To be able to handle these type of materials within numerical simulations tools for the injection moulding process, accurate rheological information is needed. Within this investigation, a dual bore rheometer and a reverse engineering technique on an injection moulding machine are used to determine industrial relevant rheological data. On the injection molding machine, the characterization is performed using a tensile bar mould equipped with pressure and temperature sensors. Finally, the compatibilized material is used to produce an industrial part through injection moulding during the processing, pressure and temperatures are registered within the mould. Good correlation is found between experimental data and numerical simulation results using the new rheological data.