Applications of “Forced Rayleigh Scattering” and “Photon Correlation Spectroscopy” for the examination of transport properties in polymer melts

The importance of optical techniques for the characterization of the dynamics in polymers has increased in the last 10 years. This was caused by the rapid development in optics and microelectronics which has made these techniques easily available and extremely precise. However, in case of the examination of transport properties in bulk polymers, new difficulties arise due to the comparably slow dynamics underlying these phenomena. The topic of this paper is a small survey of two optical techniques which can be applied to solve the arising problems and a presentation of some results of our working group concerning slow translational transport processes in polymers. In a first part, the technique of “Forced Rayleigh Scattering” will be discussed according to two selected examples, the self-diffusion of polymers can the mobility of small molecules in glassy polymers. In the second part, some peculiarities “Photon Correlation Spectroscopy” applied in the bulk will be treated.