| Abstract: | An improved Coulter Counter procedure is described for determining the size distribution and volume fraction of the elastomeric discrete phase in high-impact polystyrene. The method isolates the discrete phase from a dispersion of the whole polymer in DMF by centrifugation and redisperses the discrete phase in an aqueous surfactant solution, thus allowing the particles to deswell and resume the dimensions they had in the polystyrene matrix. By measuring a Coulter Counter size distribution on the aqueous dispersion, a discrete-phase volume fraction can be reliably derived for the original impact polystyrene. The method is rapid and precise. |
