Rheological Studies on Virgin and Metallized Unsymmetrical Dimethyl Hydrazine Gelled Systems

Abstract Rheological studies on unsymmetrical dimethyl hydrazine‐methyl cellulose gelled system have been conducted under varying shear rates in order to establish its flow characteristics. The gel is found to behave as a pseudoplastic thixotrop. The viscosity build‐up with respect to time has been traced till apparently a firm gel is set. The viscosity is found to increase with time rapidly in the beginning and minor changes are observed thereafter. The effect of temperature and extent of metal (Al and Mg) loading on apparent viscosity of the gelled system has also been investigated. Both the apparent viscosity and thixotropic character of the virgin gel are found to decrease with increase in temperature. An increase in rate of shear decreases the apparent viscosity significantly. The thixotropic character of the metallized gelled systems is observed to increase with metal content and that they exhibit a shearthinning behaviour too. Power law has been applied to assess the variation of pseudoplastic index n and consistency index K with temperature and metallization. The results reveal that n increases with temperature and decreases with metal loading whereas K shows an opposite trend. The yield value of gelled systems is noted to show decrease with temperature and increase with metal incorporation.