Comparison of the influence of fluorocarbon and hydrocarbon surfactants on the adsorptions of SDS, DTAB and C _(12)E _8 at the air/water interface by MD simulation

摘要

Adsorptions of sodium dodecylsulfate (SDS), dodecyltrimethylammonium bromide (DTAB) and octaethylene glycol monododecyl ether (C _(12)E _8) at the air/water interface in the presence of hydrocarbon and fluorocarbon surfactants (HCEP and FCEP) were investigated by molecular dynamics (MD) simulation. With the addition of HCEP or FCEP, the monolayer is more organized than in individual surfactant systems. Extremely expanded C _(12)E _8 chain in a smaller tilt angle is discovered in C _(12)E _8/HCEP system. In SDS or DTAB systems, relatively small tilt angle of surfactants is observed in the presence of FCEP. Their analog, a silicone surfactant DSEP shows a favorable effect on interfacial properties with DTAB.