Transient Inhomogenities in Polymeric Liquids and Solutions - Characterization by Static and Dynamic Light-Scattering

Abstract

Low molecular weight liquid polyisoprenes and concentrated solutions of polystyrene in toluene were studied by static and dynamic light scattering. Besides the well known density and concentration fluctuations, both systems show an additional slow relaxation mode which is accompanied by a strong scattering at small angles. The relaxation rate of the process is proportional to the square of the scattering vector q. The process seems to be due to the motion of clusters inside the sample. Small angle light scattering experiments indicate a cluster size of the order of 10(-7) m. After several months the clusters disappeared. For the samples under study, cluster formation therefore constituted a non-equilibrium phenomenon.