MODELING OF PACKING BEHAVIOR OF IRREGULARLY SHAPED PARTICLES DISPERSED IN A POLYMER MATRIX

The dependency of the rheological properties of highly concentrated su spensions on solid concentration and particle size distributions was i nvestigated using a high pressure capillary rheometer. The maximum pac king fractions estimated based on rheological measurements for irregul ar shaped particles were compared with the maximum packing fractions o btained for spherical particles having similar particle size and size distributions. This was done in order to understand the effect of sphe ricity on the packing behaviour of irregular particles. The maximum pa cking fractions of the spherical particulate systems were obtained by a mechanical vibration technique as well as by rheological measurement s. The Ouchiyama and Tanaka model for spherical particles was modified to predict the maximum packing fractions of irregularity shaped parti culate systems using the concept of packing diameter. The modified mod el was verified with experimental results obtained for bimodal irregul arly shaped as well as spherical particles.