title: Molecular dynamics simulations of SDS, DTAB, and C12E8 monolayers adsorbed at the air/water surface in the presence of DSEP.
abstract: The properties of adsorbed monolayers of three hydrocarbon surfactants with the same hydrophobic tail, sodium dodecyl sulfate (SDS), dodecyltrimethylammonium bromide (DTAB) and octaethylene glycol dodecyl ether (C(12)E(8)) at the air/water surface in the absence and presence of a dimethylsiloxane ethoxylate-propoxylate (DSEP) were studied via molecular dynamics simulations to compare the effect of the headgroups on the aggregation behaviors of surfactant mixtures. The structures and dynamical properties of the monolayers were greatly affected after adding DSEP. In the presence of DSEP, SDS monolayer was better ordered and more compact, whereas C(12)E(8) monolayer was relatively disordered. Some DTAB molecules immerged into water, and the others adsorbed at the surface were in less compact but well-ordered arrangement. The reason for the appearance of different types of monolayers was also discussed, with the goal of providing a theoretical approach for their further applications.
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan 250100, PR China.
authors.forename: Jinyu
authors.initials: J
authors.lastname: Pang
authors.forename: Yajing
authors.initials: Y
authors.lastname: Wang
authors.forename: Guiying
authors.initials: G
authors.lastname: Xu
authors.forename: Tingting
authors.initials: T
authors.lastname: Han
authors.forename: Xin
authors.initials: X
authors.lastname: Lv
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang