Molecular dynamics simulation on the structure–activity relationship between the Gemini surfactant and foam properties

Abstract The structure–activity relationship between the molecular structure of Gemini surfactants and foam properties has not yet been deeply revealed. In this study, we clarified for the first time the structure–activity relationship between foam properties and molecular structure of Gemini surfactant by discussing the variation characteristics of parameters such as free energy of interface formation, radial distribution function, and mean square displacement calculated by molecular simulation method. The research results show that (1) the Gemini surfactant with the sulfonic acid head group has the most excellent foam properties; (2) the foam properties increase monotonously with the increase of the hydrophobic tail chain length; (3) the foam properties decrease monotonously with the increase of the spacer group length. It is hoped that this article can further broaden the application range of surfactants as foaming agents in industrial fields such as oil and gas exploitation.