In PVC, a distinction is made between the hard PVC and the soft PVC, which also applies to different areas. Special attention is paid to the thermal degradation of the PVC. Plastics are now blended with fillers to improve their physical and chemical properties. In the case of organically modified montmorillonites (OMMT), however, it is the case that these decompose at 150 C. On the basis of nucleophilic substitution or Hofmann elimination, these can accelerate PVC degradation. The extrusion parameters were thus adjusted, so that thermal degradation was prevented. In addition to the optimization of the processing parameters, fillers were also added and extruded at the same parameters. On the basis of rheology it was possible to assess how the sample behaves under mechanical stress. In addition to the amplitude test, frequency tests were also carried out. The LVE (linear viscoelastic range) was determined by the amplitude test. The amplitude test gives information not only through the plateau (LVE range), but also on failures in micro- and macroscale. At a temperature of 165 C and nitrogen flooding of the measuring chamber the measurements were finally carried out. The frequency test was carried out with a constant deformation of 0.4% and a frequency range of 0.1 to 628 rad s-1. PVC and its nanocomposites are solid structures at 165 C, which is particularly evident in the viscosity curve. This is aimed at an infinitely high value at low frequencies. Furthermore, a tendency of the fillers to agglomerate formation could be determined by means of scanning force microscopy. At 5% by mass of filler, agglomerate formation is to be expected. This was also the case with the topography images and the corresponding 3D images. The reason for this is that there is a lack of space in the polymer and therefore the fillers are joined together.