Source Year: 1996

Mixtures of disperrsions and grafted latices are usually chemically heterogeneous and have not only a distribution of partice size but also of particle density. The analysis of such products by analytical ultracentrafugation, by determining the sedimentation coefficient distributions of the sample in two isorefractive dispersing media of different densities, is described. It is shown to be possible to determine the particle size and particle density distributions simultaneously ie for each particle size of the size distribution, the correlated particle density can be determined. This is demonstrated for a number of samples. The method is shown to represent a major development in the study of the structure of more complicated dispersions. The composition of latex mixtures can thus be analysed and a valuable insight gained into the mechanism of grafting reactions.