Dynamic adsorption influences drop and bubble formation of Polymer Surfactant Complexes

Surface tension of a freshly created interface varies due to dynamic adsorption that is intimately linked with the rate of mass transfer of surfactant from liquid sub-phase to the interface, and this adsorption-limited kinetics impacts the formation of drops and bubbles. Complexation of a neutral polymer to an ionic surfactant in solution influences dynamic adsorption, surface tension and bulk rheological response. Dynamic surface tension refers to the time dependent variation in surface tension, that can be characterized using conventional methods like pendant drop analysis, Wilhelmy plate, etc. However, the conventional methods are limited in their temporal resolution. In this study, we utilize maximum bubble pressure tensiometry for the measurement of dynamic surface tension at extremely short (1-50 ms) timescales. We characterize the adsorption kinetics of charged surfactants as well as surfactant-polymer complexes. We characterize the pinch-off dynamics of bubbles and drops to determine the influence of shear and extensional rheology behavior as well as dynamic adsorption on foamability, emulsion formation and processability.