(543b) Atomistic Simulations of Micellization and Adsorption of Imidazoline-Based Surfactants Near Metal-Water Interfaces

Imidazoline-based surfactants are popular corrosion inhibitors in the oil and gas industry. These molecules are known to strongly adsorb onto the metal-water interfaces, as well as form micelles in the aqueous phase. High degree of corrosion inhibition is observed at concentrations close to critical micelle concentration (CMC). However, molecular underpinnings of the relationship between micellization and surface adsorption are not completely understood. By employing atomistic representation of imidazoline-based surfactants in explicit water, we have studied micellization and transport properties of these molecules as a function of concentration, size of the alkyl tail and ionic strength. Furthermore, we have investigated the adsorption characteristics of these molecules at the metal-water interface at different concentrations. We find that the micelle forming tendency of these molecules depends strongly on the length of the alkyl tail and the ionic strength of the solution. The dynamic equilibrium between adsorption at the metal-water interface and micellization will be discussed.