physical properties of some powder's formulations

Abstract

It is well known that there is a sound correlation between moisture content of a powder and physical properties such as flow, cohesivness, porosity, packing, strength of van der waals forces and electrical charges. Experiments were carried out with series of ten powder formulations (Contain : Kaolin, talc, starch, zinc oxide,zinc stearate and sodium bicarbonate). Relationship of their properties to the samples are measured and discussed for samples one to five quantity of kaolin and talc flactuate between 5% to 75% for formulations 6 to 10, starch and kaolin have the same flactuations as first ones. Water was added to the samples in amount of 0% , 1% , 2% ... 10%, according to the plotes of bulk density versus number of taps at different water content, some samples are in different position from the others. Porosity for formulation 1 to 10 decrease as moisture is increased, but bulk density increased except for 0% and 10% moisture for samples 4,5,9 and 10. Repose angle for formulations and 6 contain 2% moisture indicated that electrostatic charge quite decreased, therefore flowability of these samples increased. Furthermore it is proven that samples contain kaolin is much more hygroscopic than formulations contain talc and starch.