Molecular dynamics simulations of inverse sodium dodecyl sulfate (SDS) micelles in a mixed toluene/pentanol solvent in the absence and presence of poly(diallyldimethylammonium chloride) (PDADMAC)

We have performed a 15 ns molecular dynamics simulation of inverse sodium dodecyl sulfate (SDS) micelles in a mixed toluene/pentanol solvent in the absence and presence of a cationic polyelectrolyte, i.e. poly(diallyldimethylammonium chloride) (PDADMAC). The NAMD code and CHARMM force field were used. During the simulation time, the radii of SDS inverse micelles changed and the radii of the water droplets have been calculated. The behavior of SDS hydrocarbon chains has been characterized by calculating the orientation order parameter and the chain average length. The water droplet properties (water flow, water molecules displacement) have been examined. In summary the MD simulations indicate a more rigid and ordered surfactant film due to the formation of a polyelectrolyte palisade layer in full agreement with the experimental findings, e.g. the viscosity increase and shift of the percolation boundary.

Graphical abstractAn aqueous SDS-micelle dissolved in a toluene/pentanol mixture in the presence of a cationic polyelectrolyte has been examined using MD simulations.Figure optionsDownload full-size imageDownload high-quality image (132 K)Download as PowerPoint slideResearch highlights► We have done a molecular dynamics simulation of a complex system in toluene/pentanol solvent. ► The main structural and dynamical properties have been examined. ► The computer simulation study is in full agreement with experimental data.