Investigations on the influence of metal surfaces on the degradation of Polystyrene
Sprache des Vortragstitels:
Advances in Polymer Science and Technology
Sprache des Tagungstitel:
It is well known for a long time, that polymers (here: Polystyrene) show degradation under thermal stress. This thermal degradation is well studied and there are different methods, mechanisms and possibilities how this works established. Nowadays it seems to be proven, that there are more different parameters or chemicals which can influence the degradation of polystyrene. Recently problems in the processing showed, that there could be an influence of the material of the processing tool/machine as well.
The aim of these investigations was, to show that metal / the interaction of polymer and metal has an impact on the progress of the degradation of polystyrene. This should be shown with rheological experiments / techniques. The experiments were implemented in a plate-plate rheometer, in which plates of different materials (material of an extruder screw) were attached, so that the behavior of the polymer could be observed.
The analysis was done under the same circumstances as oszillatory rheological measurements are normally done. Meaning, that first timetest were made afterwards amplitudesweeps and then frequencysweeps. The evaluation of the 2 preliminary examinations showed that the frequencysweeps could be done using the whole variety of possible parameters. Initially the measurements with the normal rheometer plates were carried out and then these with the obtained plates out of extruder screw material. Both measurements were made with and without Nitrogen, for the purpose of comparison without changing the plates. There weren´t significant differences between the measurement with the different plates, using a Nitrogen-atmosphere (no degradation). Continuing with the comparison of the two different results without nitrogen one can say that there seems to be an impact of the material / the interaction of the material with the polymer in the progress of the mechanism of the degradation.