Non-equilibrium states in polyelectrolyte-surfactant systems at fluid interfaces: A critical review

Over the last two decades, a significant body of research has been developed trying to understand the association and properties of mixtures formed by oppositely charged polyelectrolytes and surfactants. Particular emphasis has been given to their interfacial properties and the intriguing formation of nonequilibrium states. The synergy between these components at interfaces has attracted considerable attention due to its relevance in various industrial and biological applications. The combination of oppositely charged entities leads to complex interactions that influence the stability and behavior of interfaces. This review critically examines recent advances toward understanding the interfacial behavior when polyelectrolytes and surfactants coexist. Emphasis is placed on the existence of nonequilibrium states, shedding light on transient phenomena and kinetic aspects that play a crucial role in the overall system behavior. This will provide insights into the mechanisms governing the interfacial phenomena in these mixed systems. In summary, this review will contribute to the fundamental understanding of colloidal and interfacial science, offering a valuable perspective on designing and optimizing materials with tailored properties.