Rheological Characterization of Cassava Starch under Shear Stress with Magnetic Particle Enhancement

This research explores the rheological behavior of cassava starch, focusing on its dilatant and pseudoplastic responses under varying shear stresses and shear rates, with and without the influence of a magnetic field. The study aims to empirically validate theoretical projections by determining the power law exponent, which characterizes the starch’s flow behavior, and to examine its viability for functional applications, particularly in protective materials such as military gear. Two cassava starch varieties were locally obtained and manually processed. A base sample of 20g was prepared and subjected to rheological evaluation. Subsequently, iron filings were incorporated at 2g and 4g concentrations to investigate the influence of magnetic particulates on viscosity. Flow behavior analysis was conducted by applying the linearized form of the power law model, and data visualization was executed using Microsoft Excel. Findings demonstrate that cassava starch at a 20g concentration displays shear-thinning (pseudoplastic) behavior. Upon the addition of iron fillings, an increase in the power law exponent was observed, signifying heightened apparent viscosity and greater resistance to flow under applied stress. These results suggest that magnetic additives significantly influence the rheological profile of cassava starch, enhancing its potential as a tunable non-Newtonian fluid. The study concludes that cassava starch, inherently pseudoplastic, can be effectively modified with magnetic components to exhibit tailored flow characteristics, offering promising implications for smart materials designed to absorb and dissipate impact. Future investigations are recommended to refine the formulation and assess its integration into real-world protective systems.