Published online by Cambridge University Press: 10 February 2011
Photon correlation spectroscopy in the depolarized mode has been used to monitor the reorientational dynamics of Aroclor (A 1248) (polychlorinated biphenyls) that contain in solutions various amounts of low and high molecular weight (Mw) polymers. For the high Mw polymer/A1248 solutions we observe a very small dependence of the stretched exponential parameter β on temperature. In contrast, the low Mw polymer/A 1248 solutions display a pronounced temperature dependence of β. These preliminary experiments allow us to use the effect of modification of the solvent dynamics by added polymer to estimate the length scale of cooperative motion in glass forming systems from the size of the polymer chain.