Effect of clay-zwitterionic interactions in controlling the viscoelastic properties in organomodified clays

Investigating the rheology of 2D materials such as clays is of growing interest in various applications as it dictates their flowability and structural stability. Clay minerals present unique rheological properties, especially when in suspension. This study explores the effect of functionalizing bentonite clay with betaines of variable carbon chain lengths on the rheological properties of clay slurries to analyze their interactions in suspension. The results show that these zwitterion-functionalized clays exhibit higher viscosity, storage moduli, and flow stresses due to the formation of three-dimensional networks and increased aggregation caused by intercalation. The structural properties of the clay slurries are also found to be pH-sensitive. Additionally, XRD and SEM analyses support the proposed intercalation of the clays. The findings suggest the potential application of small-chain betaine functionalized clays in engineering and energy applications. Overall, this study provides insight into predicting the stability and strength of functionalized clay suspensions.